Class notes for pyp 001 semester 132 (3)

King Fahd University of Petroleum & Minerals – Prep Year
Preparatory Physical Science & Engineering Program - (132) Semester
Course Name & Code: Preparatory Physical Science - PYP001
Textbook: “Physical Science, Exploring Matter & Energy” by G. de Mola.
 Course Coordinator:
 Dr. Tayseer Abu Alrub Office: Building 58 Ground Floor Room 0019
 Telephone: 7083 (office) E-mail: taburrub@kfupm.edu.sa
 Instructor Name: Jawad M Ahmad Office: Building 58 Ground Floor Room 0011
Telephone: 7623 (Office) E-mail: jawadahmad@kfupm.edu.sa
 Course Website: http://www.kfupm.edu.sa/sites/phypyp/default.aspx
 Course Description Introduction to basic concepts of Physics (Newton’s laws of motion;
momentum & energy; work & power; waves; electricity& magnetism) and Chemistry (states of
matter; properties of matter & atomic structure; radioactivity & nuclear reactions and their
applications); water resources as a selected topic from Earth Science.
 Course Objectives:
 Review basic concepts in Physical Sciences through which students would be equipped with
general English scientific terminology.
 Develop and stimulate students’ interest in Physical Sciences.
 Engage students in reading scientific text.
 Attendance is compulsory. It will be enforced and evaluated according to current university
regulations. DN grade shall be given to students who accumulate 5 or more unexcused absences
or a total (excused and unexcused) of 8 or more absences. A student, who has a valid excuse for
an absence, must present an officially authorized document to his instructor no later than one
week following his resumption of classes. No excuses will be accepted after posting the final
grades.
 Grading Policy:
Class Work 20% (Attendance 2%, Class Quizzes 8%, Online Quizzes 5% & Online Home
Works 5%)
Major Exam I 20% [Week 06]
Major Exam II 20% [Week 11]
Final Exam 40% [Saturday, May 24, 2014 at 12:30 PM]
__________________________
Total 100%
 Teaching Method: Lectures-Blackboard, Multimedia (Power Point Presentations), WebCT-eLearning,
Interactive and/or Group Work, Practical Demonstrations.
 Make-up Exam Policy: A student, who misses an exam, must present an official and valid
document (excuse) to the instructor within 7 days after the exam so as to be eligible for a make-up.
If not, the score for that exam will be zero. Personal excuses will not be accepted.
 Cheating is unethical. Proved cases of cheating would entitle concerned students to zero marks
(in exams or other assessments) and the possibility of dismissal from the University.
By Jawad Ahmad Page 1

PYP001 Syllabus and Lecture Schedule [UW] - (Term 132)
Course Name & Code: Preparatory Physical Science- PYP001
Textbook: “Physical Science, Exploring Matter and Energy” by G. L. de Mola
Week DATE TOPIC SECTION * HW
1
26-01-14
29-01-14
Introduction
Classifying Matter, Elements
---
2.1, 2.2
HW-1
2
02-02-14
05-02-14
Physical Properties, Physical Changes
Chemical Properties, Chemical Changes
3.1, 3.2
3.3, 3.4
HW-2
3
09-02-14
12-02-14
Solids, Liquids
Gases, Changes of State
4.1, 4.2
4.3, 4.4
HW-3
4
16-02-14
19-02-14
Improvements to the Atomic Model,
Properties of Subatomic Particles
Radioactivity, Nuclear Decay and Radiation
5.2, 5.3
11.1, 11.2 HW-4
5
23-02-14
26-02-14
Nuclear Reactions and Their Uses
Measuring Motion, Velocity and Acceleration
11.3
12.1, 12.2
HW-5
6
02-03-14
05-03-14
Velocity and Acceleration, Momentum
What is Force? Friction
12.2, 12.3
13.1, 13.2
HW-6
7
09-03-14
12-03-14
Gravity
Gravity, Newton’s Laws of Motion
13.3
13.3, 13.4 HW-7
8
16-03-14
19-03-14
Newton’s Laws of Motion
Work and Power
13.4
15.1
HW-8
Midterm Vacation 23-27, March, 2014
9
30-03-14
02-04-14
What is Energy?, Energy Conversions
Energy Conversions, Energy Resources
16.1, 16.2
16.2, 16.3
HW-9
10
06-04-14
09-04-14
The Nature of Waves, Types of Waves
Types of Waves, Properties of Waves
19.1, 19.2
19.2, 19.3
HW-10
11
13-04-14
16-04-14
The Nature of Sound, Properties of Sound
What is an Electromagnetic Wave?,
The Electromagnetic Spectrum
20.1, 20.2
21.1, 21.2 HW-11
12
20-04-14
23-04-14
The Electromagnetic Spectrum, Producing light
What is Electric Charge?, Static Electricity
21.2, 21.3
23.1, 23.2
HW-12
13
27-04-14
30-04-14
Making Electrons Flow, Electric Power
The Nature of Magnets, Making Magnets
23.3, 23.5
24.1, 24.2
HW-13
14
04-05-14
07-05-14
Earth as a Magnet
Magnetism from Electricity, Electricity from
Magnetism
24.3
25.1, 25.2
HW-14
15
11-05-14
14-05-14
Water Resources
Water Resources
Chapter 26 (#) HW-15
Final Exam: Saturday, 24/05/2014, at 12:30 PM.
* Section 2.1 = Chapter two, section one
# Chapters 26 is not from the textbook, it will be provided by the department.

PYP001 Syllabus and Lecture Schedule [MR] - (Term 132)
Course Name & Code: Preparatory Physical Science- PYP001
Textbook: “Physical Science, Exploring Matter and Energy”by G. L. de Mola
Week DATE TOPIC SECTION * HW
1
27-01-14
30-01-14
Introduction
Classifying Matter, Elements
---
2.1, 2.2
HW-1
2
03-02-14
06-02-14
Physical Properties, Physical Changes
Chemical Properties, Chemical Changes
3.1, 3.2
3.3, 3.4
HW-2
3
10-02-14
13-02-14
Solids, Liquids
Gases, Changes of State
4.1, 4.2
4.3, 4.4
HW-3
4
17-02-14
20-02-14
Improvements to the Atomic Model,
Properties of Subatomic Particles
Radioactivity, Nuclear Decay and Radiation
5.2, 5.3
11.1, 11.2 HW-4
5
24-02-14
27-02-14
Nuclear Reactions and Their Uses
Measuring Motion, Velocity and Acceleration
11.3
12.1, 12.2
HW-5
6
03-03-14
06-03-14
Velocity and Acceleration, Momentum
What is Force? Friction
12.2, 12.3
13.1, 13.2
HW-6
7
10-03-14
13-03-14
Gravity
Gravity, Newton’s Laws of Motion
13.3
13.3, 13.4 HW-7
8
17-03-14
20-03-14
Newton’s Laws of Motion
Work and Power
13.4
15.1
HW-8
Midterm Vacation, 23-27, March 2014
9
31-03-14
03-04-14
What is Energy?, Energy Conversions
Energy Conversions, Energy Resources
16.1, 16.2
16.2, 16.3
HW-9
10
07-04-14
10-04-14
The Nature of Waves, Types of Waves
Types of Waves, Properties of Waves
19.1, 19.2
19.2, 19.3
HW-10
11
14-04-14
17-04-14
The Nature of Sound, Properties of Sound
What is an Electromagnetic Wave?,
The Electromagnetic Spectrum
20.1, 20.2
21.1, 21.2 HW-11
12
21-04-14
24-04-14
The Electromagnetic Spectrum, Producing light
What is Electric Charge?, Static Electricity
21.2, 21.3
23.1, 23.2
HW-12
13
28-04-14
01-05-14
Making Electrons Flow, Electric Power
The Nature of Magnets, Making Magnets
23.3, 23.5
24.1, 24.2
HW-13
14
05-05-14
08-05-14
Earth as a Magnet
Magnetism from Electricity, Electricity from
Magnetism
24.3
25.1, 25.2
HW-14
15
12-05-14
15-05-14
Water Resources
Water Resources
Chapter 26 (#) HW-15
Final Exam: Saturday, 24/05/2014, at 12:30 PM.
* Section 2.1 = Chapter two, section one
# Chapters 26 is not from the textbook, it will be provided by the department.

Semester 132 Schedule
PYP 001
Building 61
Sunday & Wednesday Monday & Thursday
Time Room 107 Room 108 Room 107 Room 108
8:00 am Musazay
Section 1
Tayseer
Section 2
Musazay
Section 3
Tayseer
Section 4
9:00 am Jawad
Section 5
Tayseer
Section 6
Musazay
Section 7
Tayseer
Section 8
10:00 am Ashraf
Section 9
Saleem
Section 10
Jawad
Section 11
Saleem
Section 12
11:00 am Ashraf
Section 13
Saleem
Section 14
Jawad
Section 15
Saleem
Section 16
Lunch
12:50 pm Ashraf
Section 17
Jawad
Section 18
Jawad
Section 19
Ashraf
Section 20
1:50 pm Ashraf
Section 21
Jawad
Section 22
Jawad
Section 23
Ashraf
Section 24
3:00 pm Musazay
Section 25
Saleem
Section 26
Musazay
Section 27
Saleem
Section 28
4:00 pm Musazay
Section 29
Saleem
Section 30
Musazay
Section 31
Ashraf
Section 32

Class Notes 132 Semester
Write your name and student ID on the front page and back page of your textbook.
Go on Blackboard every week to do your online homework and online quiz.
The course website is http://www.kfupm.edu.sa/sites/phypyp/default.aspx
These notes are not a substitute for reading the book. Read the book.
Chapter 2 Types of Matter
2.1 Classifying Matter
 Matter: Anything that has mass and volume. Mass is the amount of stuff in an object and
has units of kilograms. Mass and w⃑⃑⃑ eight are not the same thing. The volume of an object is
the number of cubes in a 3D object and has units of meters cubed m3.
 What is not matter? Some examples of things that are not matter are light, heat,
electromagnetic waves (see page 357), and sound.
Pure Substances
 Molecule: A particle created/formed when two or more atoms combine. A molecule is not a
single atom. A molecule is created when two or more atoms combine like N2, H2, CO2, H2O,
etc. The atoms combining can be the same (N2 or H2) or different (CO2 or H2O).
 Compound: A pure substance in which two or more different elements combine. Examples
of a compound are carbon dioxide CO2, ammonia NH3, table salt NaCl, and water H2O. The
atoms have to be different. The ratio of elements in a compound is always the same.
 All compounds are molecules but not all molecules are compounds. A molecule is formed
when two or more atoms join together chemically. A compound is a molecule that contains
at least two different elements. (From http://education.jlab.org/qa/compound.html)
 Ratio: Examples: Water (H2O) has two H atoms for each one O atom. For every five games a
football team plays, they lose two games. This is a ratio of 5:2. For every 16 hours I am
awake, I sleep 8 hours. This is a ratio of 16:8.
 Element: An object/substance in which all of the atoms are the same. See pages 94-95.
 Pure Substance: Object made of only one type of particle. Examples of a pure substance are
a gold bar, silver coin, pure water, pure carbon dioxide, etc. A pure substance can be an
element or a compound.
 All elements are pure substances but not all pure substances are elements.
Mixtures
 Mixture: An object that is made of several substances that can be separated physically.
Example: A fruit salad. You can mix different fruits together but they don’t physically
combine. You can separate the fruits with your hand.
 Mixtures do not always have the same ratio of the substances that make them up. For
example, if you buy a fruit salad and give some of the fruit salad to your friends, some
friends may have more of one type of fruit than other friends.
 Heterogeneous Mixture: Different materials/objects in a mixture that can be seen easily.
Examples of a heterogeneous mixture are sand and soil, water and oil, and a fruit salad.
 Homogeneous Mixture/Solution: Different materials/objects in a mixture that cannot be
seen easily. Examples of homogeneous mixtures are air, ocean water, antifreeze, Pepsi and
tea.
 See Figure 2.4 on page 23 and memorize it.

2.2 Elements
 An element is a pure substance made up of only one type of atom. An element is the
simplest type of pure substance. Example: A gold bar.
Discovery of Elements
 There are 117 known elements. 92 are found in nature. The rest are made artificially in a
laboratory which are unstable and exist for only a short time.
Describing Elements
 The name of an element is abbreviated by a chemical symbol. The chemical symbol for iron
is Fe, gold is Au, silver is Ag, etc. See Figure 6.4 on pages 94-95.
 In a chemical symbol the first letter is always capitalized. The second letter is always
lowercase.
The Makeup of Elements
 See the periodic table of elements (Figure 6-4 on pages 94-95.).
 An element is made up of atoms.
 We need electrons e-, protons p+, and neutrons to make an atom. The basic model of an
atom is a spherical (A sphere is a three dimensional 3D circle.) object with neutrons n and
protons p+ in the center of the sphere (nucleus) and a cloud of electrons e- outside the
center. See Figure 2.7 on page 26.
 An element is defined by the number of protons p+ in its nucleus. Hydrogen H will always
have one proton p+. Hydrogen H may have 100 neutrons n or 1000 electrons e- but it will
always have one proton p+.
 What if a hydrogen H atom has two protons p+? Then we have a helium He atom, not a
hydrogen H atom.
 What’s the definition of gold Au? Gold Au will always have 79 protons p+. That’s the
definition of gold. Silver Ag will always have 47 p+. Elements are defined by the number # of
protons p+ in its nucleus.
 We can only see objects that are longer than the wavelength of visible light. Since the
length of an atom is shorter than the wavelength of visible light we cannot see atoms with
our eyes or with a microscope. We cannot see atoms directly. The diameter (diameter =
2 × radius) of an atom is about 2 × 10−10 m = 0.2 nm.

Chapter 3 Properties of Matter
3.1 Physical Properties
 A physical property of an object is a characteristic/description that can be observed/seen
without changing the compounds or molecules of an object into different compounds or
molecules.
 A property of an object is a characteristic/trait/feature that can be used to describe the
object. Some examples of a property of an object is if it is large or small, the color, whether
it is flammable or not, etc.
Observable Properties
 An observable property of an object is a characteristic of an object that you can determine
by using your senses: sight, touch, sound, smell, or taste. Some examples of an observable
property are the color of an object, whether it is rough or smooth, hard or soft, and its state
of matter (Is the object a solid, liquid, gas, or plasma?).
Measurable Properties
 You cannot determine the length, mass, volume, boiling point, melting point, density, or
specific gravity of an object by using your five senses. You have to use an instrument/tool to
find this out. A measurable property is when you need an instrument/tool/object to
determine a characteristic of an object.
 The density of an object is the mass of an object divided by its volume. ρ =
mass
volume
kg
m3].
= [
See Figure 3.4 on page 42.
 The specific gravity of an object is a ratio of the density of an object to the density of
another object. specific gravity =
ρobject 1
⁄ . Question: What are the units of
ρobject 2
specific gravity?
Kinds of Properties
 An intensive property is a property that does not depend on the amount of matter present.
The boiling point, melting point, temperature, and color of an object are examples of
intensive properties.
 An extensive property is a property that depends on the amount of matter present. The
mass and volume of an object are two examples of extensive properties.
 The book gives a good example of taking a small amount of water from a swimming pool
(Figure 3.5 on page 43.) to compare the two properties.
3.2 Physical Changes
 A physical change is when an object changes how it looks without changing its composition
(The molecules and compounds in an object don’t change). Some examples are cutting
wood, bending a wire, blowing up a balloon, stretching a rubber band, breaking glass, etc.
Changes of State
 H2O being converted from solid ice to liquid water is another example of a physical change.
The object/compound is still H2O.
 A change of state is a physical change since the molecules or the compounds of an object do
not change.

3.3 Chemical Properties
 A chemical property describes how the molecules or compounds of an object changes (or
doesn’t change) when it interacts with other objects or energy.
 An example of a chemical property is silver tarnishing (See Figure 3.10 on page 47.) or iron
rusting (See Figure 3.11 on page 48.).
 Another example of a chemical property is when iron is combined with nitrogen gas at room
temperature and nothing happens.
 You cannot determine a chemical property just by looking at an object. A chemical property
is determined/observed only when the molecules or compounds of an object changes.
 Flammability is another chemical property. This is when an object will burn, or catch on fire,
easily. Objects that catch on fire easily are flammable. Pure oxygen, gasoline/petrol, and
paper are flammable.

3.4 Chemical Changes
 A chemical change occurs/happens when one type of matter changes into another type of
matter.
 In a physical change the properties of the original object are the same as the properties of
the new object.
 In a chemical change the properties of the original object are different from the properties
of the new object. Example: Hydrogen and oxygen are both flammable but H2O is not
flammable.
 The new substance/object cannot be changed/converted to the old substance/object easily
in a chemical change.
 An example of a chemical change is when hydrogen burns in oxygen. H2O is formed. The
H2O cannot easily be changed to hydrogen and oxygen easily. It will take a lot of energy and
time to do this.
Chemical Properties vs. Chemical Changes
 A chemical property is when an object has the ability to change the molecules or compounds
in it. A chemical change is when the molecules or compounds in an object are
altered/changed.
 An example of this is petrol/gasoline. Petrol is flammable. That is a chemical property. A
chemical change is when the petrol burns.
 Another example is iron. Iron rusts. That is a chemical property. A chemical change is when
the iron rusts.
Chemical Changes All Around
 Some examples of chemical changes are the burning of a candle, food cooking, fruit
ripening, silver tarnishing, iron rusting, copper forming patina, etc.
 In caves H2O and CO2 combine to form carbonic acid which can break rocks. See the figure
on page 40.
 In photosynthesis, which is a chemical change, plants convert CO2 and H2O to sugar and O2.
The energy that makes this happen comes from the sun.
 In cellular respiration animals and humans use O2 to break down sugars into energy.
 Energy is what we need to do work. Work is when we move an object. See chapters 15 and
16.
Signs of Chemical Change
 There are some signs that tell us that a chemical change may have occurred/happened.
 If the total amount of energy in an object decreased, or if energy is released, then a chemical
change may have occurred/happened. Example: Light is released from an object.
 If a gas is formed then a chemical change is likely to have happened. Example: An antacid or
vitamin c tablet is dropped in water.
 Sometimes a solid is formed/created when two liquids are mixed together. This is called
precipitate. This is a chemical change.
 A chemical change may occur when the color of an object is changed. Example: A half eaten
apple changes color.
 The change in smell, or odor, of an object is another sign that a chemical change may have
taken place. Example: Rotten eggs.
Conservation of Mass
 The law of conservation of mass states that the total amount of mass in the whole universe
is constant. Mass can be converted to energy.
Read the Chapter 3 Summary on Page 52.

Chapter 4 States of Matter
 Matter exists in different states (solid, liquid, gas, plasma) and can change from one state to
another when it gains or releases energy. Example: Water.
 Question: Which particle has the most energy? A solid, liquid, or gas?
 All atoms are in constant motion. Some atoms move more than other atoms, meaning some
atoms have a larger speed than other atoms.
 Solids, liquids, and gases (states of matter) are determined by how fast particles move and
how strongly they are attached to each other.
 More than 99% of matter in the universe is plasma. Plasma is found in stars because it
exists at high temperatures. Plasma is created artificially in fluorescent bulbs, neon lights,
and in plasma screen televisions. It is seen naturally in lightning.
4.1 Solids
 The three states of matter on Earth are solids, liquids, and gases.
Characteristics of a Solid
 Solids have a definite shape and a definite volume. If you move a solid, the shape and size
will not change. The particles in a solid are packed tightly in fixed positions. The particles
move but they only vibrate about a fixed position.
Types of Solids
1. Crystalline solid: Particles are in an organized/repeating 3D order/pattern. See Figure 4.3 on
page 57. Examples: Salt, sugar, sand, and ice.
2. Amorphous Solid: Particles are not arranged (not organized) in any order/pattern.
Examples: Rubber, glass, and wax.
4.2 Liquids
 Lava is rock in a liquid state. Lava comes from volcanoes. When lava cools it becomes rock.
Characteristics of a Liquid
 Liquids have a definite volume but no definite shape. Liquids take the shape of the
container. Liquid particles have enough energy to move past one another.
 Particles in a liquid move more quickly/rapidly than particles in a solid.
Surface Tension
 Sometimes a small animal can walk/float on water. How is this possible? The surface
tension is created when uneven f orces (a push or a pull) act on the particles at the surface
of a liquid. See Figure 4.6 on page 59.
 Water particles pull other water particles toward each other. The water particles on the top
have no other particles to pull toward it from above. Because of this a thin film (or a thin
layer) is created at the surface of the liquid.
 If only a small amount of liquid is present then the surface tension pulls the liquid into a
spherical shape.
 The Jesus Lizard can run on water.
 In order to mimic the lizard, a human would need to run at almost 30 meters per second, "a
velocity beyond human ability." A man would also need "an average power output almost 15
times greater than the maximum sustained power output for humans."
http://www.popularmechanics.com/technology/digital/fact-vs-fiction/water-runner-physics-debunked
Viscosity
 Viscosity is the f orce of friction of a liquid, or its resistance to flow.
 The viscosity of a liquid depends on the attraction between its particles. The stronger the
attraction between its particles, the slower the liquid flows and the greater the viscosity of
the liquid will be.
 Example: The viscosity of honey is greater than the viscosity of water.

4.3 Gases
 A gas has no definite volume and no definite shape. A gas will move rapidly/quickly and gas
particles will have a great distance from one another.
 Just like a liquid, a gas will take the shape of the container that it is in.
 Diffusion is a uniform/constant spreading of gas. Gas fills a room of any dimensions.
Gas Pressure
 A f orce is a push or a pull.
 Pressure=Force/Area=[Newton/m2]=[Pascals]
 Compression occurs/happens when you increase the number of particles in a constant/fixed
volume or when you decrease the volume of an object with a fixed number of gas particles
inside it.
 The opposite of compression is decompression, or when you decrease the number of
particles in a constant/fixed volume or when you increase the volume of an object with a
fixed number of gas particles inside it.
 Directly Proportional Relationship: As x increases, y increases. Y=KX (X and Y are variables
and K is a positive constant.) Example: The more money I have, the more friends I have. The
less money I have, the fewer friends I have. The more money I have, the more handsome I
am. The less money I have, the less handsome I am.
 Inversely Proportional Relationship: As X increases, Y decreases. Y=K/X (X and Y are
variables and K is a positive constant.) Example: The less I exercise, the more mass I have.
The more I exercise, the less mass I have. The more time I spend watching football, the less
time I have time to study. The less time I spend watching football, the more time I have to
study.
Boyle’s Law
 Boyle’s Law: If the number of molecules of a gas in a container is constant and the
temperature of the gas is constant, then the volume of the gas is inversely proportional to
the pressure of the gas. See Figure 4.10 on page 61.
Charles’s Law
 Charles’s Law: If the number of molecules of a gas in a container is constant and the
pressure of the gas is constant, then the volume of the container is directly proportional to
the temperature of the container. Example: If you increase the temperature of the gases in
a tire, the tire will pop. See Figure 4.11 on page 62.
 Charles’s Law and Boyle’s Law can be seen from the Ideal Gas Law PV=nRT, where
P=Pressure, V=Volume, n=number of molecules of gas, R=Constant, and T=Temperature.
 Absolute zero occurs when the temperate of an object is 0 Kelvin (or -273.15°C). At
absolute zero all particles stop moving.
 The current world record was set in 1999 at 100 picokelvins (pK), or 0.000 000 000 1 of a
Kelvin, by cooling the nuclear spins in a piece of rhodium metal.
http://en.wikipedia.org/wiki/Absolute_zero

4.4 Changes of State
 A change of state the conversion of a substance/object from one state to another (Example:
Solid  Liquid, Solid  Gas, and etcetera). The molecules or compounds of the object does
not change as it converts from one state to another. For example, water (liquid) that turns
to ice (solid) will still have the chemical composition as H2O.
Energy
 Energy is something that lets us do work. We do work when we move an object (work =
F⃑
orce ×d⃑
isplacement).
 A change of state requires a change in energy. If we convert an object from a solid to a
liquid, the object will gain energy since a liquid moves more than a solid. If we convert an
object from a liquid to a solid, the object will lose energy since a solid will move more slowly
than a liquid.
 Kinetic energy is the energy of a moving object. The kinetic energy of a moving object is
given by the equation KE =
1
2
mv⃑ 2, where m is the mass of the object and v⃑ is the velocity of
the object. If the object is at rest then the kinetic energy of the object is 0 Joules.
 The thermal energy of an object is the total kinetic energy of all the particles in a
sample/group. Thermal energy is absorbed (taken in) or released (lost) when an object
changes from one state to another.
 Heat is the thermal energy that is transferred/moved from one substance/object to another.
 Matter gains thermal energy when it is heated (Example: Solid  Liquid or Liquid  Gas or
Solid  Gas). Matter loses thermal energy when it is cooled (Example: Liquid  Solid or
Gas  Liquid or Gas  Solid).
 The temperature of an object is the average kinetic energy of all the particles in a
sample/group.
Melting
 Melting is the change of state from a solid  liquid. When an object melts it gains energy.
 The melting point of an object is the temperature at which a substance/object changes from
a solid to a liquid.
 Amorphous solids (glass, wax, rubber, and plastics) don’t have a definite/exact melting
point.
 Crystalline solids (salt, sugar, sand, ice, quartz) have a definite/exact melting point.
Freezing
 Freezing is the change of state from a liquid  solid. When an object freezes it loses
energy.
 The freezing point of an object is the temperature at which a substance/object freezes.
 Since freezing is the reverse/opposite of melting, the freezing point = melting point.
Vaporization
 Question: Why do people perspire/sweat? Pigs do not perspire/sweat, so how do they cool
off? What about dogs?
 Vaporization is the change of state from a liquid  gas. When an object vaporizes it gains
energy.
 There are two types of vaporization:
1. Boiling is vaporization that occurs/happens throughout a liquid (Example: Boiling
water to make tea.). The boiling point of an object is directly proportional to the
pressure.
2. Evaporation is vaporization that occurs/happens at the surface of a liquid and at
temperatures below the boiling point of a substance (Example: Perspiring/sweating
or water evaporating in a lake.).

Condensation
 Condensation is the change of state from a gas  liquid. During condensation a gas loses
energy.
 Since condensation is the opposite of boiling, the condensation temperature =
vaporization temperature.
Sublimation
 Sublimation is the change of state from a solid  gas. During sublimation an object gains
energy. Example: Dry ice is carbon dioxide CO2 in a solid state. The dry ice turns from a solid
to a gas when it is exposed to room temperature.
Analyzing a Heating Curve
 An endothermic process is a process that requires an absorption/gain of energy (Example:
Melting, vaporization, and sublimation). Eating is an example of an endothermic reaction
since you’re gaining energy when you eating.
 An exothermic process is a process that requires a release/loss of energy (Example: Freezing
and condensation.). Exercising is an example of an exothermic reaction since you’re losing
energy when you exercise.
 See Figure 4.19 on page 67:
 In area A of the graph the ice will absorb (take in) heat and will go from -20°C ice to 0°C ice.
 In area B of the graph the ice goes from 0°C solid ice to 0°C liquid water. During the change
of state the temperature of the object does not change as the solid ice melts to liquid water.
It takes energy to convert the object from solid ice to liquid water. At 0°C the object can be
solid ice or liquid water.
 In area C of the graph heat will be absorbed (taken in) by the liquid water starting at 0°C and
the heat will increase the temperature of the liquid water until its temperature is 100°C.
 At 100°C the object goes from 100°C liquid water to 100°C gas vapor. The temperature of
the water does not change as the liquid water vaporizes. It takes energy to convert the
object from liquid water to a gas vapor. At 100°C water can be a liquid or a gas.

 Summary:
Energy ↓
Exothermic
State Energy ↑
Endothermic
↗
Deposition
Freezing ↗
Solid
↙ Melting
↙
Sublimation
Liquid
Condensation ↗
↙ Vaporization
Gas
http://www.chemistry.wustl.edu/~edudev/LabTutorials/Thermochem/Fridge.html
Read the Chapter 4 Summary on Page 68.

Chapter 5 The Atom
5.2 Improvements to the Atomic Model
 Ernest Rutherford theorized that electrons travel around the nucleus. The problem with this
idea is that electrons, which are negatively charged, would eventually lose energy, slow
down, and fall into the nucleus of the atom where it is attracted to the positively charged
protons.
Bohr’s Atomic Model
 Niels Bohr theorized that electrons revolve/move around the nucleus in circular orbits that
are a fixed/specific distance from the nucleus. The amount of energy the electron has
depends on the distance it is from the nucleus. The electron in an atom has more energy
the farther away it is from the nucleus. The electron does not lose any energy while
traveling around the nucleus.
 Bohr’s Model was based on the work of Max Planck. Planck theorized that energy levels
were not continuous but discrete. Because of this theory Bohr theorized that the electron
could only be in specific orbits around the nucleus.
Bohr’s Evidence
 When a photon γ with enough energy hits an electron in an atom the electron will move to a
higher energy level (orbit/radius) in an excited atom. This is called photon absorption.
 After a short time the electron will move back to its original position/orbit/radius. The
energy lost by the electron will leave as a photon γ. This is called photon emission.
http://astrocosmosci.files.wordpress.com/2012/07/photon-emission-absorption.jpg
 In an experiment by Johann Jakob Balmer, hydrogen gas was sealed in a tube and a current
was given to the hydrogen gas to excite it. The hydrogen gas then produced light. When
this light is passed through a slit vertical lines called emission spectrum lines are visible.
These emission spectrum lines are specific/unique to each element and are the elements
fingerprints.

Principal Energy Levels and Sublevels
 There are seven principal energy levels, or orbits. Niels Bohr suggested that the principal
energy levels may have sublevels, labeled s, p, d, and f.
 The s sublevel can hold up to two electrons, the p sublevel can hold up to six electrons, the d
sublevel can hold up to ten electrons, and an f sublevel can hold up to 14 electrons.
http://chemwiki.ucdavis.edu/Inorganic_Chemistry/Electronic_Configurations
Chadwick’s Contributions
 The mass of an atom was measured to be much higher than expected. James Chadwick
found that the nucleus of the atom contains a particle with no charge. This particle is named
the neutron and has a mass that is slightly greater than the mass of a proton.
 The new model of the atom has neutrons and protons at the center of the atom and
electrons outside the nucleus moving in discrete circular orbits.
Modern Atomic Theory
 Scientists now had to find the exact distance the electrons are from the nucleus. This is very
difficult to do since the atomic nucleus and electrons are so small. Finding the exact
location/position of an electron will change its velocity. Finding the exact velocity of an
electron will change its location/position. Because of this it is impossible to know the exact
location and velocity of an electron. Because of this we draw an electron cloud to tell us the
possible location an electron can be.

5.3 Properties of Subatomic Particles
 Atoms are made up of electrons, neutrons, and protons.
Atomic Size
 We have never seen an atom because the diameter of an atom is smaller than the
wavelength of visible light. The diameter of an atom is about 2 × 10−10 m = 0.2 nm. We
can only see objects that are longer than the wavelength of visible light.
 Since we cannot see an atom directly we need to use alternative/other methods to
understand the shape of an atom. A scanning tunnel microscope uses an electronic surface
to scan a surface. See Figure 5.15 on page 84.
Atomic Number
 The atomic number, or the number of protons in an atom, is the definition of an element.
 Hydrogen will always have one proton, helium will always have two protons, lithium will
always have three protons, etcetera.
 Atoms are electrically neutral, meaning that the total charge of an atom is 0 coulombs. This
means that the number of protons is equal to the number of electrons in an atom.
Isotopes
 Hydrogen will always have one proton. Sometimes hydrogen is found with zero neutrons (H-
1), sometimes hydrogen is found with one neutron (H-2), and sometimes hydrogen is found
with two neutrons (H-3).
 Atoms with the same number of protons and different number of neutrons are isotopes of
each other. See Figure 5.17 on page 85.
Mass Number
 The mass number of an atom is the number of neutrons plus the number of protons in an
atom.
 The atomic notation tells us the name of the atom (chemical symbol), how many protons
are in the atom (atomic number), and the number of neutrons plus protons (mass number)
in the atom.
79 is gold with 79 protons and 197 neutrons plus protons. It doesn’t matter if
 The atom 197Au
the smaller number is on the top or bottom. The larger number is always the number of
neutrons plus protons (mass number) and the smaller number is always the number of
protons (atomic number), so197Au
79 = 197 79
Au .
 We can find the number of neutrons in an atom by subtracting the atomic mass from the
mass number.
Atomic Mass
 The atomic mass unit has replaced the kilogram in atomic mass measurements since the
mass of an atom is small and people don’t like to calculate small numbers.
 The atomic mass is the average mass of a naturally occurring element.

Chapter 11 Nuclear Chemistry
11.1 Radioactivity
 Question: What is radioactivity?
 Radioactivity occurs/happens when an unstable atom emits (give off) particles and energy.
The Nucleus
 Question: How are protons and neutrons held together in the nucleus?
 Answer: Protons and neutrons are held together in the nucleus by the strong 퐟 퐨퐫퐜퐞. The
strong f orce has a very short range/distance. As the distance increases the strong f orce
decreases.
 At short distances the strong f orce is stronger than the electromagnetic f orce. At longer
distances the electromagnetic f orce is stronger than the strong f orce.
Forces and Stability
 The strength of the strong f orce decreases as the number of protons in the nucleus
increases. Because of this more neutrons are in atoms with a large number of protons.
 The red line on Figure 11.2 on page 178 is called the “Band of Stability.” This is the neutron
to proton ratio that gives stable atoms. Atoms outside this red line are unstable/radioactive.
 Unstable/unbalanced atoms want to decay. Radioactive decay is when an unstable nucleus
spontaneously/suddenly emits matter and energy. A nucleus is unstable when the neutron
to proton ratio is outside the band of stability and when the strong f orce is not great enough
to hold the nucleus together.
Radioactive Decay
 All elements with 84 or more protons decay. That means they are all radioactive.
 Uranium has 92 protons.
 Transuranium elements are elements with 93 or more protons. They are all unstable and
are rarely found in nature. They are made in laboratories and decay/decompose almost
immediately/instantaneously after they are formed/created.
 All elements have radioactive isotopes. It depends on its neutron to proton ratio.
Isotopes and Radioisotopes
 Isotopes are atoms with the same number of protons but different number of neutrons.
 Radioisotopes are isotopes that are unstable and decay.
 All elements have isotopes and some of these are radioisotopes.
 All isotopes of an element have the same chemical properties.
Describing Nuclei
 The atomic number is the number of protons in the nucleus of an atom.
 The mass number is the total number neutrons plus protons in an atom.
 Example: In 6C
12 , C is the chemical symbol, 6 is the atomic number, and 12 is the mass
6 . Just remember that the
number. The above chemical symbol can also be written as 12C
smaller number is the number of protons in the nucleus and that the larger number is the
number of neutrons plus protons in the nucleus.
11.2 Nuclear Decay and Radiation
 Chemical Reactions involve changes in electron number. Mass is conserved.
 Nuclear Reactions involve changes in nuclei. Mass is not conserved. Some mass will
convert to energy.
 In both chemical and nuclear reactions the reactants are on the left side and the products
are on the right side of the equation. Example: A + B  C. Both A and B are reactants while
C is a product.

Nuclear Radiation
Alpha α Particles
 An alpha α particle is the nucleus of the helium atom. An alpha α particle has two protons
and two neutrons. It has a charge of +2. In nuclear equations an alpha α particle is shown as
He 2 4
238 → Th 90
. Example: 92U
234 + He 2 4
Beta β Particles
0 .
 A beta β particle is an electron. In nuclear equations a beta β particle is shown as −1e
131 → Xe 54
Example: 53I
131 + e −1
0 . In β decay, a neutron becomes a proton and an electron
leaves the atom.
Gamma γ Rays
 A gamma γ ray is high energy electromagnetic radiation. A gamma ray has much more
2 energy than 4
visible light (See Figure 21.7 on page 357.). A gamma ray is not a particle
because it has no mass or electric charge. Gamma γ rays are commonly emitted with alpha
and beta particles during nuclear decay. Example: 230 90Th
→ 226 88
Ra + He + γ
Penetrating Power
 Question: Why do you have to wear a heavy shirt when you get an x-ray at the hospital?
 Alpha α particles are easy to stop. Gamma γ rays are the most difficult to stop. The cost to
stop a gamma γ ray is much greater than to stop an alpha γ particle or beta β particle. See
Figure 11.6 on page 181.
Transmutation
 Transmutation is the process in which one element changes into another element through
nuclear decay.
 Sometimes a radioactive element will go through many decays before become stable. See
 In artificial transmutation fast moving particles hit the nucleus of an atom to form new
elements. All the transuranium elements have been created by artificial transmutation.
Half-Life
 The half-life of a radioisotope is the time it takes for one-half of the atoms to decay (or
convert to energy).
mfinal
minitial
1
2
= (
n
)
 where mfinal is the final mass of the radioactive object, minitial is the initial mass of the
object, and n is the number of half-lives that have been completed on the object. See Figure
11-8 on page 183.
11.3 Nuclear Reactions and Their Uses
Nuclear Fission
 Nuclear Fission occurs/happens when a big atom breaks/decays into smaller atoms.
Mass and Energy
 Mass is not conserved in nuclear fission. The total mass of the large atom before the
reaction is greater than the total mass of the two smaller atoms after the reaction. The
missing mass is converted to energy. This is why nuclear reactions are much more powerful
than chemical reactions. See Figure 11-9 on page 184.
Chain Reactions
 In a chain reaction, the first action is linked/connected to the next action. See Figure 11.10
on page 185.
 A nuclear explosion will occur/happen if there is an uncontrollable nuclear chain reaction in
a large mass of material. A lot of energy can be created from this and nuclear power plants
use fission reactions to produce electricity.

Nuclear Power Plants
 Nuclear power plants produce a large amount of electricity without polluting air (unlike coal
or gas) or water.
 Unfortunately nuclear power plants produce radioactive waste that has a half-life of
thousands of years.
Nuclear Fusion
 Nuclear Fusion occurs/happens when two small mass atoms combine to form/create one
large mass atom. The total mass of the two small atoms before the reaction is greater than
the total mass of the one larger atom after the reaction. The missing mass is converted to
energy. See Figure 11.12 on page 186.
 Nuclear fusion produces more energy than nuclear fission.
Temperature and Fusion
 To get two nuclei to combine is very difficult because of the electric repulsion (Repel is the
opposite of attract.). This can only happen if the two small atoms are traveling at high
speeds. These high speeds only happen when the temperature is great (like millions of
degrees). This great temperature only occurs/happens in stars.
Solar Fusion
 The fusion reaction in the sun (which is a star) occurs in several steps.
 Each second the sun (which is a star) will fuse 600 million tons of hydrogen into 596 million
tons of helium. The missing 4 million tons of matter is converted to energy.
Fusion Reactions on Earth
 A fusion power source would be ideal/perfect/best since it would not pollute the air and the
waste will be minimal/smallest.
 Unfortunately only short-lived fusion reactions have been produced here in laboratories on
Earth.
Detecting Radiation
 Unfortunately we can’t see, hear, smell, taste, or feel/touch radiation.
 To minimize radiation we have to minimize our time next to a radioactive source, maximize
our distance from a radioactive source, and put something between us and the radioactive
source. This is called time, distance, and shielding.
 People use film badges, Geiger counters, and electronic sensors to detect and measure
radiation.
Nuclear Medicine
 Cancer cells can be destroyed by exposing it to radiation. Unfortunately this kills both
healthy and unhealthy cells.
 Radioisotopes can be used as tracers to image parts of the human body. See Figure 11.14 on
page 187.
Nuclear Storage Tank in Washington is Leaking Radioactive Waste
http://www.businessinsider.com/nuclear-storage-tank-in-washington-is-leaking-radioactive-waste-
2013-2#ixzz2L8jrpLDN

Chapter 12 What is Motion?
12.1 Measuring Motion
 Every object that is at rest on Earth is actually moving 30 km/s relative to the sun. Your
speed depends on who is watching you.
Motion and Position
 The position of an object is the location of an object.
 An object is in motion when it changes its position/location.
Reference Point
 The reference point is the location where you are making a measurement. Example: The car
is going 60 km/hr relative to the man at rest on the ground. The man at rest on the ground
is the reference point.
Relative Motion
 Relative motion is the speed and direction of an object with respect to another object.
Example: A man at rest on the ground sees a plane flying 500 km/h while the plane (which
feels like it is at rest) sees the man running at -500 km/h.
Displacement
 The distance is the Σ length an object moves (scalar: # only).
 The 퐝 isplacement is the length and direction an object moves (퐯⃑ ector: # and direction). The
length of the 퐝 isplacement is the difference between the final location and the
initial/beginning location.
 See Figure 12-4 on page 195.
Speed
Average Speed
 The average speed of an object is the Σ distance an object travels divided by the Σ time it
takes to travel that distance. The units of average speed are [distance/time].
Instantaneous Speed
 The instantaneous speed of an object is the speed at an exact moment/time. Example: The
speedometer in a car. See Figure 12.5 on page 196.
Graphing Motion
 The slope of a line is the change in the y distance divided by the change in the x distance.
slope = m =
Δy
Δx
=
yfinal − yinitial
xfinal − xinitial
 If the x-axis on a graph represents the time it takes an object to travel and the y-axis on a
graph represents the distance an object travels then the slope of a line on the graph is the
speed of the object. The greater the slope the greater the speed of the object. See Figure
12-6 on page 197.

12.2 퐕⃑⃑ 퐞퐥퐨퐜퐢퐭퐲 and 퐀⃑⃑ 퐜퐜퐞퐥퐞퐫퐚퐭퐢퐨퐧
퐕⃑⃑ 퐞퐥퐨퐜퐢퐭퐲
 The v⃑ elocity of an object gives the speed and direction of an object. V⃑⃑ elocity is a vector,
meaning it has both a number and direction.
v⃑ elocity = v⃑ =
Δ d⃑
isplacement
Δ time
=
d⃑
final −d⃑
initial
tfinal − tinitial
= [distance/time]
 Since the above equation is a v⃑ ector we can break it up into three parts:
vx =
Δdx
Δt
=
dx f − dx i
tf − ti
vy =
Δdy
Δt
=
dy f − dy i
tf − ti
vz =
Δdz
Δt
=
dz f − dz i
tf − ti
Adding 퐕⃑⃑ 퐞퐥퐨퐜퐢퐭퐢퐞퐬
 You can add or subtract two velocities when one object is on top of the other and the two
objects move in the same or opposite direction. Example: See Figure 12-8 on page 198.
퐀⃑⃑ 퐜퐜퐞퐥퐞퐫퐚퐭퐢퐨퐧
 A change in the v⃑ elocity of an object is called a⃑ cceleration. a⃑ ≠ 0
m
s2 when you speed ↑,
slow ↓ (deceleration), or Δ direction (since a⃑ cceleration is a v⃑ ector). Example: See Figure
12-9 on page 199 and Figure 12-11 on page 201.
 Example: An object moving in a circle with a constant speed has a changing v⃑ elocity and a
nonzero a⃑ ccereration.
Calculating 퐀⃑⃑ 퐜퐜퐞퐥퐞퐫퐚퐭퐢퐨퐧
a⃑ cceleration = a⃑ =
Δ v⃑ elocity
Δ time
=
v⃑ final − v⃑ initial
tfinal − tinitial
= [
distance/time
time
] = [distance/time2]
ax =
Δvx
Δt
=
vx f − vx i
tf − ti
ay =
Δvy
Δt
=
vy f − vy i
tf − ti
az =
Δvz
Δt
=
vz f − vz i
tf − ti
Graphing 퐀⃑⃑ 퐜퐜퐞퐥퐞퐫퐚퐭퐢퐨퐧
 If the x-axis on a graph represents the time it takes an object to travel and the y-axis on a
graph represents the speed of an object then the slope of a line on the graph is the
a⃑ cceleration of the object. The greater the slope the greater the a⃑ cceleration of the object.
See Figure 12-11 on page 201.
12.3 퐌⃑⃑⃑ 퐨퐦퐞퐧퐭퐮퐦 퐩⃑⃑
kg ∙ m
m⃑⃑⃑ omentum = p⃑ = mass × v⃑ elocity = m × v⃑ = [
s
]
px = m × vx py = m × vy pz = m × vz
 The m⃑⃑⃑ omentum p⃑ of an object is directly proportional to its mass and v⃑ elocity.
Conservation of 퐌⃑⃑⃑ 퐨퐦퐞퐧퐭퐮퐦 퐩⃑⃑
 If there is only one external f orce on a group of objects then p⃑ initial = p⃑ final. See Figure
12.12 on page 202.
Collisions Between Objects
 When two objects hit each other and there are no other external f orces on the two objects
then m⃑⃑⃑ omentum p⃑ will transfer from one object to another. Example: Billiard balls. See

Chapter 13 Nature of 퐅 퐨퐫퐜퐞퐬
13.1 What is 퐅 퐨퐫퐜퐞?
 A 퐟 퐨퐫퐜퐞 is a push or a pull. A f orce is a v⃑ ector (like v⃑ elocity and a⃑ cceleration) so it has both
a number and direction. The unit of f orce is the Newton.
Types of 퐅 퐨퐫퐜퐞퐬
 A contact 퐟 퐨퐫퐜퐞 is a f orce when two objects are touching each other.
Examples:
1. A book on a table.
2. A man pushing a wall.
3. A ball rolling on the ground.
 An action-at-a-distance 퐟 퐨퐫퐜퐞 is a f orce when two objects are not touching each other.
Examples:
1. If you jump up the Earth pulls you down even though you are not touching the Earth.
This is the f orce of gravity.
2. Two electrons repel each other even though they are not touching each other. An
electron and a proton attract each other. This is the electric f orce.
3. Two magnets can attract or repel each other even though they are not touching each
other. This is the magnetic f orce.
Combining 퐅 퐨퐫퐜퐞퐬
 Because a f orce is a v⃑ ector, f orces add and subtract. See Figure 13.2 on page 208.
 The net 퐟 퐨퐫퐜퐞 of an object is the sum/total of all the f orces on an object.
Balanced 퐅 퐨퐫퐜퐞퐬
 Balanced 퐟 퐨퐫퐜퐞퐬 are f orces on an object that add up to zero. This means that a⃑ = 0
m
s2 and
v⃑ = constant.
Examples:
1. Pushing a book at rest. The f orce of the push on the book is equal in number/magnitude
but opposite in direction as the f orce of friction. F⃑
push +F⃑
friction = 0 N  F⃑
push =
−F⃑
friction  a⃑ = 0
m
s2  v⃑ = constant.
2. Pushing a book at a constant speed in a straight line. F⃑
push +F⃑
friction = 0 N  F⃑
push =
−F⃑
friction  a⃑ = 0
m
s2  v⃑ = constant.
 Remember that for balanced f orces ΣF⃑
ext = 0 N, a⃑ = 0
m
s2, and 퐯⃑ = 퐜퐨퐧퐬퐭퐚퐧퐭. The object
can be at rest or moving in a straight line at the same speed if the f orces on it are balanced.
Unbalanced 퐅 퐨퐫퐜퐞퐬
 Unbalanced 퐟 퐨퐫퐜퐞퐬 are f orces on an object that don’t add up to zero. Example: Pushing
horizontally on a book. If the f orce of the push on the book is greater than the f orce of
friction between the book and the table then we have an unbalanced f orce on the book.
F⃑
push +F⃑
friction > 0 푁  F⃑
push > −F⃑
friction  a⃑ ≠ 0
m
s2  v⃑ ≠ constant
Balanced 퐅 퐨퐫퐜퐞퐬
ΣF⃑
ext = 0 N
a⃑ = 0
m
s2
v⃑ = constant
Unbalanced 퐅 퐨퐫퐜퐞퐬
ΣF⃑
ext ≠ 0 N
a⃑ ≠ 0
m
s2
v⃑ ≠ constant

13.2 The 퐅 퐨퐫퐜퐞 of Friction
 The F⃑
friction resists motion on an object.
 F⃑
friction always points opposite the direction of motion.
 The F⃑
friction always slows an object down.
Factors Affecting Friction
 A rough surface has a high F⃑
friction while a smooth surface has a low F⃑
friction.
Types of Friction
 Static friction is the F⃑
friction of between an object at rest and the surface it is resting on.
 Sliding friction is the F⃑
friction between a moving object and the surface it is moving on.
 The static friction of an object is much greater than the sliding friction of an object.
Example: The F⃑
push needed to move a book at rest on a horizontal table is much greater
than the F⃑
push needed to move the same book if it’s already moving.
 Fluid friction (viscosity) is the F⃑
friction of a fluid. A fluid can be a liquid or a gas.
 Rolling friction is the F⃑
friction of a rolling object. The F⃑
friction of a rolling object is much less
than the F⃑
friction of a sliding object or a static object. Example: It takes much more f orce to
move a heavy truck at rest than to keep the same truck moving if it is already moving.
Using Friction
 Friction is helpful because it slows objects down. See Figure 13.7 on page 211.
Reducing Friction
 Friction can sometimes be bad because it will convert useful kinetic energy (or moving
energy) into useless heat. Air, oil, and ball bearings are all used to reduce the F⃑
friction
between two objects. See Figure 13.8 on page 211.

13.3 The 퐅 퐨퐫퐜퐞 of Gravity
The Study of Gravity
 The F⃑
gravity is the attraction between two objects with mass.
Law of Universal Gravitation
 Law of Universal Gravitation: The gravitational f orce = F⃑
gravitational =
Gm1m2
r2 . G = 6.67 ×
10−11 N×m2
kg2 , m1 and m2 are the masses of the two objects, and r is the distance between
the two objects.
 The gravitational f orce is directly proportional between the mass of the objects and
inversely proportional to the distance between the two objects. Example: If you double the
distance between two objects, the F⃑
gravitational will decrease by 4.
Falling Objects
For a falling object we have two cases:
1) When 퐚⃑ = 퐠⃑ : Free Fall
 An object is in free fall if the object is in the air with the only external f orce being the f orce
of gravity F⃑
gravity.
 There is no air f riction F⃑
friction when the object is in free fall.
 In free fall the object can be moving up, down, or at any angle.
 If you drop two objects with different masses from rest at the same height/elevation in free
fall the two objects will reach the ground at the same time. See Figure 13.14 on page 216.
 If you drop an object from rest in free fall on Earth the speed vs. time graph would look like
this:
120
100
80
60
40
20
0
Speed (m/s) vs. Time (s) in Free
Fall (No Air Friction)
0 2 4 6 8 10 12
 The speed of the object increases by 9.8 m/s every second. The slope of this graph gives you
the a⃑ cceleration of the object which is 9.8 m/s2.

2) When 풂⃑⃑ < 품⃑⃑ : Non-Free Fall (or Air Resistance)
 Air resistance is the f orce of friction from air.
 If an object is moving up on Earth both the F⃑
gravity and the F⃑
friction point down.
 If an object is falling down on Earth the F⃑
gravity points down and the F⃑
friction points up.
 The F⃑
friction of a falling object is directly proportional to the velocity of the object. As the
v⃑ elocity of an object increases so does the F⃑
friction. Example: When you stick your head out
of the window of a fast moving car your head is pushed back more than when you stick your
head out of the window of a slow moving car.
 The terminal 퐯⃑ 퐞퐥퐨퐜퐢퐭퐲 of an object is when an object is falling down and the
magnitude/number of the F⃑
gravity down is equal to the magnitude/number of the F⃑
friction
up.
 When an object reaches its terminal velocity, ΣF⃑
y = 0 N, a⃑ y = 0
m
s2, and v⃑ = constant. See
 The terminal v⃑ elocity of an object depends on size and shape of the object.
 Example: An object falls from rest with F⃑
friction. As t ↑, v⃑ elocity ↑ and F⃑
friction ↑ also.
gravity = −F⃑
friction. ΣF⃑
y = may = Ffriction + Fgravity = 0 N.  a⃑ y =
After some time F⃑
0
m
s2.  v⃑ y = constant = terminal v⃑ elocity.
 Example: Compare the velocities of an object falling from rest with no air friction and with
air friction. Graph the results.
60
40
20
0
퐭 (퐬)
Free Fall
(No 퐅 퐟퐫퐢퐜퐭퐢퐨퐧)
퐯퐲 (퐦/퐬)
With 퐅 퐟퐫퐢퐜퐭퐢퐨퐧
퐯퐲 (퐦/퐬)
0 0 0
1 9.8 9.8
2 19.6 19.6
3 29.4 29.4
4 39.2 38
5 49 45
6 58.8 50
7 68.6 52
8 78.4 52.3
9 88.2 52.4
10 98 52.4
Speed (m/s) vs Time (s) with Air
Friction
0 2 4 6 8 10 12

 The slope of the above graph gives you the a⃑ cceleration of the object with air resistance.
The slope of the graph (or the a⃑ cceleration) starts at 9.8 m/s2 and decreases to 0 m/s2.
 When the a⃑ cceleration (or slope) is 0 m/s2 the v⃑ elocity is constant which is the terminal
v⃑ elocity of the object.
 Objects with less mass reach terminal v⃑ elocity quicker. Objects with more mass reach
terminal v⃑ elocity at later times. Example: Example: An elephant, human, and ball are all
dropped from rest at the same time. The elephant will reach the ground first. Then the
human. Then the ball. The mass, shape, and the volume of the objects matter.
퐖⃑⃑⃑ 퐞퐢퐠퐡퐭 Versus Mass
 The mass is the amount of stuff an object has. Mass is a scalar so it has only a number and
no direction. Mass has units of kilograms.
 The 퐰⃑⃑ 퐞퐢퐠퐡퐭 of an object is the F⃑
gravity at the surface of a planet. W⃑⃑⃑ eight is a vector so it
has both a number and direction. The direction of w⃑⃑⃑ eight always points down towards the
center of the planet. W⃑⃑⃑ eight is a f orce so it has units of Newtons.
 W⃑⃑⃑ eight = F⃑
gravity = m × g⃑ = [kg ×
m
s2] = [Newton]
 g⃑ Earth = 9.8
m
s2.
 W⃑⃑⃑ eight changes from location to location but mass doesn’t. Your mass on Earth and your
mass in space are the same. Your w⃑⃑⃑ eight on Earth and your w⃑⃑⃑ eight in space are different
since g⃑ is different from Earth and space.
 Doctors don’t know what they are talking about when they ask you for your w⃑⃑⃑ eight.
Doctors should ask you for your mass. This is why the periodic table of elements has units of
mass and not w⃑⃑⃑ eight.
 Question: Is g⃑ = +9.8
m
s2 or g⃑ = −9.8
m
s2 on Earth?
 Answer: g⃑ always points to the center of the Earth. If the +y axis is pointing up then g⃑ =
−9.8
m
s2. If the +y axis is pointing down then g⃑ = +9.8
m
s2.

13.4 Newton’s Laws of Motion
Newton’s First Law of Motion: The Law of Inertia
 Inertia is the resistance to change in motion. Objects will not change their speed and
direction (or v⃑ elocity) unless there is an external f orce on the object.
 The law of inertia states/says that an object at rest will be/remain at rest forever unless
there is an F⃑
external. A moving object will continue to move in a straight line with the same
speed forever unless there is an F⃑
external.
 Example: A rock moving in space will move at the same speed in a straight line forever
unless there is an F⃑
external. A football on Earth will move at the same speed in a straight line
forever unless there is an F⃑
external. The reason why a football on Earth slows down and
stops is because of the F⃑
friction.
 Objects do not like to change what they are doing unless there is an F⃑
external. An object will
speed ↑, slow ↓, or Δ direction if ΣF⃑
external ≠ 0 N.
 Inertia is directly proportional to the mass of the object. If mass ↑, then the inertia ↑. If
mass ↓, then the inertia ↓.
 Example: It’s better to fight a small person with a small mass than a larger person with a
large mass because it’s easier to move the person with a small mass.
 Example: If a small car and a large truck are moving at the same speed, it will take a longer
distance for the large truck to stop than the small car because of the law of inertia. It’s
harder to get heavier objects to stop/start moving than lighter objects.
 In summary: For all objects, v⃑ elocity = constant and a⃑ = 0
m
s2 unless there is an F⃑ external.
 For all objects, the v⃑ elocity will not change unless there is an F⃑
external.
Newton’s Second Law of Motion: The Law of 퐀⃑⃑ 퐜퐜퐞퐥퐞퐫퐚퐭퐢퐨퐧
 The law of a⃑ cceleration states/says that the a⃑ cceleration of an object is directly
proportional to the sum of the external f orces on the object and inversely proportional to
the mass of the object. An object will a⃑ ccelerate in the same direction as the net/total
f orce.
ΣF⃑
ext = mass × a⃑ cceleration = m × a⃑ = [
kg × m
s2 ] = [Newton] = [N]
ΣFx = m × ax ΣFy = m × ay Σ Fz = m × az
 ΣF⃑
ext always points in the same direction as a⃑ cceleration.

Newton’s Third Law of Motion: The Law of Action and Reaction
 The law of action and reaction states/says that if you have two objects the f orce of object 1
on object 2 is equal in magnitude/number and opposite in direction of the f orce of object 2
on object 1. Newton’s third law of motion needs/requires one f orce and two objects.
+F⃑
1 on 2 = −F⃑
2 on 1
+m1a⃑ 1 = −m2a⃑ 2
Examples of Newton’s 3rd law:
1. My hand punches your face. Your face punches my hand.
2. I hit your car. You hit my car.
3. Man pushes wall →. Wall pushes man ←.
4. Man pushes chair ↓. Chair pushes man ↑.
5. Feet push ground ←. Ground pushes feet →.
6. Tires push ground ←. Ground push tires →.
7. Fish pushes water ←. Water pushes fish →.
8. Foot kicks football →. Football kicks foot ←.
9. Rocket pushes exhaust gas ↓. Exhaust gas pushes rocket ↑.
10. Earth pulls man ↓. Man pulls Earth ↑.
 Example: When you jump, the Earth pulls you down while you pull the Earth up. You cannot
see the Earth move up but you do see yourself move down because the mass of the Earth is
much greater than your mass. Because of this the a⃑ cceleration of the Earth is much less
than the a⃑ cceleration of you:
+F⃑
1 on 2 = −F⃑
2 on 1
+F⃑
man on Earth = −F⃑
Earth on man
+mmana⃑ man = −mEartha⃑ Earth
mEarth ≫≫ mman and a⃑ Earth ≪≪ a⃑ man
mEarth ≈ 6 × 1024 kg
 Newton’s second law of motion is about many f orces on one object. Newton’s third law of
motion is about one f orce on two objects.

Chapter 15 Work, Power, and Simple Machines
15.1 Work & Power
Work
 You need energy to do work. Work is done when you move an object.
Work = f orce ×d⃑
isplacement × cos θ = [Newton × meters] = [Joules]
where f orce is the push or pull of an object, d⃑
isplacement is the distance and direction the
object moves, and θ is the angle between the f orce and d⃑
isplacement. See Figure 15.4 on page
240.
 Work is the transfer of energy. Work is a scalar so it has only a number and no direction
(v⃑ ector × v⃑ ector = scalar).
 Example: You only do work if you move an object. No work is done if I push a wall that does
not move since d⃑
isplacement = 0 m. If you push an object with an angle of the f orce as 0
degrees, 45 degrees, and 90 degrees, 0 degrees will give you the most work out of the
energy you use (Example: Pushing a table horizontally.) and 90 degrees will give you no work
(Example: Pushing a table down.).
Power
Power =
work
time
=
f orce ×d⃑
isplacement × cos θ
time
= f orce × v⃑ elocity × cos θ = [
Joule
s
]
= [Watts] = [W]
where θ is the angle between the f orce and the v⃑ elocity of the object.
 Power is a scalar since v⃑ ector × v⃑ ector = scalar.
 From the above equation since time is on the denominator the power ↑ as work is done
faster.

Chapter 16 Nature of Energy
16.1 What is Energy?
Energy Makes Everything Happen
 Question: What is energy?
 Answer: Energy is the “stuff” or “thing” that we need to do work.
 Question: What is work?
 Answer: Work is done when we move an object.
Work = f orce ×d⃑
isplacement × cos θ = [Newton × meters] = [Joules]
 We need energy to do work.
 Most of the energy from Earth comes from the Sun.
Energy Units
 Both energy and work have units of Joules. Since they both have the same units they are
very closely related to each other but they are not the same.
Kinetic Energy
 The energy of a moving object is called kinetic energy.
Kinetic Energy = KE =
1
2
mv⃑ 2 = [kg
m2
s2 ] = [Joules] ≥ 0 Joules
 where m is the mass of the object in kilograms and v⃑ is the v⃑ elocity of the object in meters
per second.
 KE is directly proportional to the mass and velocity of the object. If you double the mass of
an object, the KE ↑ by 2. If you double the velocity of an object, the KE ↑ by 4.
 KE is a scalar since v⃑ ector × v⃑ ector = scalar.
Potential Energy
 The potential energy of an object is the energy stored/kept when an object moves against a
f orce. Examples: bow & arrow, spring, rubber band, fossil fuels (chemical potential energy),
electric batteries (electrical potential energy), and food (chemical potential energy).
 Gravitational potential energy is the energy of an object depending on its vertical position.
Gravitational Potential Energy = GPE = mg⃑ y⃑ = [kg
m
s2 m] = [Joule]
 where m is the mass of the object in kilograms, g⃑ is the a⃑ cceleration from g⃑ ravity in meters
per second squared, and y⃑ is the vertical distance of the object in meters.
 GPE can be positive, 0, or negative. GPE is the energy of an object with respect to its
location. GPE is directly proportional to the mass and vertical position of the object.
Forms of Energy
Thermal Energy
 Thermal energy is related to the movement or KE of particles.
Chemical Energy
 Chemical energy is the PE stored/kept in the bonds between atoms of a substance.
Example: Plants and sugars. People eating food.
Electrical Energy
 Electric potential energy is generated/created when electrons are forced together.
Electrical energy is energy that arises/comes from the movement of electric charges.
Radiant Energy
 Radiant energy is energy that comes from electromagnetic waves.
 Memorize Figure 16-6 on page 266. As you go from left to right on the figure the energy of
the wave increases.
 From Figure 16-6 we see that x-rays have high energy so they should not be taken regularly.
Gamma rays also have high energy so they will go through your body easily just like x-rays.

Nuclear Energy
 Nuclear Energy is the energy stored/kept in the nucleus of an atom. Nuclear energy holds
the particles of the nucleus together. Example: Fission & fusion releases nuclear energy.
16.2 Energy Conversions
 Energy is always being converted from one form/type to another. Example: A falling object
converts GPE to KE. Plants convert radiant energy to chemical energy. People convert
chemical energy to kinetic energy when they run.
Kinetic and Potential Energy Conversions
 The kinetic energy (KE =
1
2
mv⃑ 2) and gravitational potential energy (GPE = mg⃑ y⃑ ) of an
object can change from one form/type to another. For example, a falling object will convert
GPE to KE and a rising object will convert KE to GPE. See Figure 16-8 on page 267. If there is
no f orce of friction,
Mechanical Energy = KE + GPE =
1
2
mv⃑ 2 + mg⃑ y⃑ = Constant
 Unfortunately/sadly most energy is lost as heat.
 Read the last paragraph on page 267.
Conservation of Energy
 The law of conservation of energy states/says that energy cannot be created or destroyed.
Energy can only Δ/change form/types. Energyinitial = Energyfinal
Don’t Read Machines as Energy Converters on Page 270
16.3 Energy Resources
 Energy resources are energy sources that are used to meet the needs of the people.
Making Electricity
 KE or PE of a resource can be converted to electricity. There are several steps needed to
convert KE or PE to electricity. Some energy is lost after each step. See Figure 16-14 on
page 271.
Energy Resources from the Sun
 A renewable resource cannot be used up. See page 272. Examples: solar, wind,
hydroelectric, biomass
Solar Energy
 Solar energy is energy that comes directly from the sun.
 Solar energy is free but solar cells are expensive and inefficient.
Wind Energy
 No energy plant is necessary for wind energy and no pollution is created. Wind energy is
useful only in cleared places where there is wind. The KE of wind is converted to electrical
energy.
Hydroelectric Energy
 Water flows/moves through a dam and spins a turbine which generates/makes electricity.
 Hydroelectric energy is efficient and creates no pollution but a flowing river is needed.
Biomass
 Plant tissues used for fuel/energy are biomass fuels.
 Biomass can be burned to heat homes.
 Biomass can be converted to fuel/petroleum. Example: soy biodiesel.
 Biomass is inexpensive to grow but causes air pollution when you burn it.
Fossil Fuels
 Fossil fuels are energy resources that are from ancient/old biomass remains.
 Coal, natural gas, and petroleum are all popular forms/types of fossil fuels.
 Fossil fuels produce/make a lot of the air and water pollution on Earth.
 Fossil fuels are examples of a nonrenewable resource. A nonrenewable resource can be
used up. Example: fossil fuels, fission & fusion, and geothermal energy.

Energy from Atoms
 The strong force in the nucleus of the atom which holds the neutrons and protons together
can release a lot of energy when nuclear fusion and nuclear fission occur.
 No pollution is created during nuclear fission but radioactive waste is created.
 Nuclear fusion occurs/happens in stars. We have not learned to control nuclear fusion.
Energy from Earth
 Electricity can be generated/made using the heat from the Earth’s core/middle. This is
called geothermal power.
 A geothermal power plant is located where hot rocks lie just below Earth’s surface.
 The hot rocks convert water to steam and the steam powers a generator.
 Geothermal energy is nonrenewable but there is a lot of it.
 No pollution is produced by geothermal power plants and the cost to make electricity from it
is inexpensive.
 There are not a lot of locations where hot rocks are near the Earth’s surface.
16.4 Energy Choices
 Energy is being used more and more every day. Engineers have to find clean and
inexpensive ways to get useful energy and save energy.
Fossil Fuel Problems
 Fossil fuels (like petroleum, coal, and natural gas) are nonrenewable energy sources.
 It is getting more expensive to extract (take out) fossil fuels.
 The burning of fossil fuels creates air pollution.
 Mining coal is dangerous and many people die every year from this.
Energy Alternatives
 Every energy resource has its benefits and hazards. See Figure 16.21 on page 276.
Conservation Options
 Energy conservation is being used to reduce the amount of energy people use.
 Conserving energy reduces pollution and saves money. See Figure 16.22 on page 277.
 You can reduce, reuse, and recycle to save energy.
퐟 퐨퐫퐜퐞 ≠ 퐞퐧퐞퐫퐠퐲 ≠ 퐰퐨퐫퐤 ≠ 퐩퐨퐰퐞퐫
 A f orce is a push or a pull. F⃑
orce is a v⃑ ector and has the units of Newton’s.
 Energy is something we need to do work. Energy is a scalar and has the units of Joules.
 Work (Work = f orce ×d⃑
isplacement × cos θ) is done when we move an object. Work is a
scalar and also has the units of Joules.
 Power (Power =
work
time
=
f orce×d⃑⃑ isplacement×cos θ
time
= f orce × v⃑ elocity × cos θ) depends on
how fast we move an object. Power is a scalar and has units of Watts.
Fattest Countries in the World Revealed: Extraordinary Graphic Charts the Average Body Mass
Index of Men and Women in Every Country (with Some Surprising Results)
http://www.dailymail.co.uk/health/article-2301172/Fattest-countries-world-revealed-Extraordinary-graphic-
charts-average-body-mass-index-men-women-country-surprising-results.
html#ixzz2Qhro3dCb
The Health Effects of Drinking Soda
http://www.ionizers.org/soft-drinks.html

Chapter 19 Waves and Energy
19.1 The Nature of Waves
Waves and Vibration
 Question: How are waves created?
 Answer: Vibrations (Something moving back and forth.) produce waves that carry energy.
All waves are created from vibrations. A wave is a repeating disturbance traveling through
matter or space. Example: See Figure 19-1 on page 316.
Waves and Energy
 Since waves carry energy, they do work (work = f orce ×d⃑
isplacement × cos θ). Example:
A boat/canoe at rest in a lake moves when a wave goes under it. When the boat moves the
wave loses energy. See Figure 19.3 on page 317.
Waves and Matter
 Waves transfer energy but not matter. Example: A water wave or a rope moving up and
down. See Figure 19.3 on page 317.
Mechanical Waves
 Mechanical waves travel through matter.
 A medium is the matter in which the mechanical wave travels through.
 Example: Sound waves travel through air. The sound wave is a mechanical wave and the air
is the medium in which it travels through.
 Example: Ocean waves and water. The ocean wave is a mechanical wave and the water is
the medium in which it travels through.
 Example: A rope. A rope is a mechanical wave because it uses a rope as a medium to travel.
 In space there is no sound because space is a vacuum. A vacuum has no matter.
Electromagnetic Waves
 Electromagnetic waves can travel/move through vacuum and matter. Example: See Figure
21.7 on page 357.
 Example: In space we can’t talk to each other (using sound waves) but we can text message
each other (using electromagnetic waves).
19.2 Types of Waves
Transverse Wave
 In a transverse wave the vibration is at right angles (perpendicular) to the direction in which
the wave travels. Example: All electromagnetic waves (See Figure 21.7 on page 357.) and
some mechanical waves like water.
 See Figure 19.5 on page 319. The rope moves up and down and the wave moves to the
right. Understand what the crest/peak and trough/valley are. The peaks and valleys of the
rope are equal to the peak and valley of the hand (or cause/source).
Compressional/Longitudinal Wave
 In a compressional/longitudinal wave the vibration is parallel to the direction in which the
wave travels. See Figure 19.6 on page 320. Example: Sound waves.
 See the compression and rarefaction in Figure 19.9 on page 322.
Sound Waves
 Sound is a compressional/longitudinal wave.
 See the compression (many particles are close together) and rarefaction (many particles are
far apart) regions/areas in Figure 19.7 on page 321.
Seismic Waves
 An earthquake is called a seismic wave. A seismic wave is both a transverse wave and a
compressional/longitudinal wave. See Figure 19.8 on page 321.

19.3 Properties of Waves
The Parts of a Wave
 Figure 19.9 on page 322 shows the difference between compressional/longitudinal and
transverse waves.
Wavelength
 The wavelength λ (λ is the Greek letter lambda) of an object is the distance between two
identical/similar points on a wave.
wavelength = λ = [m]
 See Figure 19.10 on page 323.
Frequency
 The frequency of an object is the number of cycles/wavelengths that passes through a point
each second.
frequency = f =
# cycles
1 second
= [
1
seconds
] = [Hertz] = [Hz]
 Example: A computers processing speed has units of hertz.
Frequency and Period
 The period of a wave is the time it takes a wave to complete one cycle/wavelength.
Period =
# seconds
1 cycle
= [second]
 The period of a wave is the inverse of the frequency.
frequency =
1
period
period =
1
frequency
 Example: Draw a picture describing frequency and period.
Frequency and Wavelength
 See Figure 19.11 on page 324. If you move your hand up and down faster, the wavelength
↓ and frequency ↑. Since the frequency ↑, the period ↓. The wavelength and frequency
of a wave are inversely proportional to each other. The fhand = fwave.
Wave Speed
 Question: Do you see or hear lightning first? Why?
 Answer: Lightning is seen first and then heard. The speed of light is much faster than the
speed of sound.
 For sound waves: speedsolid ≫ speedliquid ≫ speedgas ≫ speedvacuum.
 Example: The speed of sound in steel is about 5,100 m/s. The speed of sound in water is
about 1,400 m/s. The speed of sound in air is about 340 m/s. The speed of sound in a
vacuum is 0 m/s.
 As temperature ↑ the speed of sound ↑ also.
 For light/EM waves: speedvacuum ≫ speedgas ≫ speedliquid ≫ speedsolid
 The speed of a wave is determined by the medium it travels through.
wavespeed = frequency × wavelength
ν = f × λ
Amplitude
 The amplitude of a wave is directly proportional to the energy of the wave. Example: See
Figure 19.3 and 19.14 on page 326.

Chapter 20 Sound
20.1 The Nature of Sound
Sound Waves
 Sound waves are compressional/longitudinal waves.
How Sound Waves Form
 Vibrating objects have kinetic energy KE =
1
2
mv2 and creates regions/areas of compression
and rarefaction. Energy is transferred by this.
How Sound Waves Travel
 Sound waves reflect and diffract/bend.
Sound Waves in Different Mediums
 Sound is a mechanical wave so it cannot travel in a vacuum like electromagnetic waves.
 For sound waves: speedsolid ≫ speedliquid ≫ speedgas ≫ speedvacuum. Example: The
speed of sound in steel is about 5,100 m/s. The speed of sound in water is about 1,400 m/s.
The speed of sound in air is about 340 m/s. The speed of sound in a vacuum is 0 m/s.
The Speed of Sound
 Sound travels by transferring energy by collisions.
Speed and Elasticity
 Elastic objects can bend/distort and return to its original shape/form.
 The speed of sound is high in elastic materials because particles in elastic objects are very
close together. This means that energy is transferred easily and quickly from one
area/region to another. Energy is transferred with little loss.
Speed and Temperature
 As temperature ↑ the speed of sound ↑ also. This is because hotter particles move faster
and transfer energy quicker than colder particles.
20.2 Properties of Sound
Frequency and Pitch
 The pitch of a sound is how high or low the sound seems to be. The pitch of a sound is
directly proportional to the frequency (frequency =
# cycles
second
= [
1
second
] = [Hz]). See Figure
20.5 and 20.6 on page 338.
Amplitude, Energy, Intensity, and Loudness
 Question: When you increase the volume the frequency of the sound wave is the same.
What changes?
 Answer: The energy of the sound wave.
Energy
 The amount of energy in a wave is directly proportional to the amplitude of the wave.
 The more particles that are in a wave the larger its amplitude and the more energy it has.
 It’s easier to see the compression and rarefaction regions/areas in a high amplitude sound
wave than a low amplitude sound wave. See Figure 20.7 on page 339.
 As the density (density =
# particles
volume
) of particles increases so does the waves energy.

Intensity
 The intensity of a wave is the amount of energy that passes through an area.
Intensity =
Energy
Area
= [
Joules
m2 ]
 A shout will produce a high intensity and high energy sound wave that can be heard from a
far distance.
 A whisper will produce a low intensity and low energy sound wave the can be heard from
only a short distance.
 Sound waves travel through collisions. After each collision some energy is lost. A shout has
more initial energy than a whisper. This is why a shout can be heard from a longer distance
than a whisper.
Loudness
 Loudness is the human perception/opinion of sound intensity. Loudness is directly
proportional to the intensity of the sound wave.
A Scale for Loudness
 The decibel dB is the unit for sound intensity.
 Anything less than 0 dB cannot be heard by humans. This is the threshold for human
hearing.
 The average speaking voice is about 60 dB.
 A 10 dB sound is 10 times greater in intensity than a 0 dB sound.
 A 20 dB sound is 10 times greater in intensity than a 10 dB sound and 100 times greater than
a 0 dB sound.
 Hearing damage occurs at 85 dB and greater. Hearing damage is permanent and
irreversible! No medicine or surgery can fix hearing damage!
The Doppler Effect
 The Doppler effect occurs when you are moving toward or away from an object that is
making noise.
 If you are moving toward an object that is making noise the wavelength (length of a wave) of
the sound will decrease and the frequency (number of cycles that pass a point per second)
will increase.
 If you are moving away from an object that is making noise the wavelength of the sound will
increase and the frequency will decrease.
 If both you and the sound source are not moving the wavelength and frequency of the
sound will not change.
http://www.physicsclassroom.com/class/waves/u10l3d.cfm
 A moving sound source or a moving listener produces the Doppler effect.

Echoes
 An echo is a reflected sound wave.
 Sonar (SOund Navigation And Ranging) uses reflected sound waves to measure distances.
Don’t Read Beats on page 342
Chapter 21 Light and Other Electromagnetic Waves
21.1 What is an Electromagnetic (EM) Wave?
Describing Electromagnetic Waves
 EM waves can travel/move in a vacuum and in matter. Mechanical waves (like water and
sound) can travel/move in matter only.
 Examples of EM waves are microwaves used by mobile phones, radio waves used by radar
speed guns (See Figure 21.1 on page 353), light we see, and the warmth we feel from the
sun.
Vibrating Source
 EM waves form when charged particles (like electrons or protons) vibrate.
Waves in Space
 Because vibrating electrons in matter are everywhere so are EM waves.
 Most EM waves are not seen or felt by people (See Figure 21.7 on page 357).
How Electromagnetic EM Waves Form
 All EM waves have electric and magnetic fields.
Force Fields
 Figure 21.2 shows three types of action at a distance f orces. These f orces don’t need to
touch an object to push or pull it and can exist in a vacuum.
Electric and Magnetic Fields
 An electric charge (like an e- or p+) that is not moving produces only an electric field.
 A moving electric charge (like an e- or p+) produces both an electric field and a magnetic
field (See Figure 21.3 on page 354). A changing magnetic field produces a changing electric
field. Changing electric and magnetic fields form EM waves.
EM Wave Formation
 An EM wave develops when an electric charge vibrates. This vibration creates both a
changing electric field and a changing magnetic field (See Figure 21.4 on page 355). A
changing electric field generates/creates a changing magnetic field and a changing magnetic
field generates/creates a changing electric field.
Properties of EM Waves
 All matter contains charged particles. Since all charged particles are vibrating, they all give
off (or emit) EM waves.
Frequency and Wavelength
 The frequency of the oscillating/moving charge is equal to the frequency of the frequency of
the EM wave.
Wave Speed
 For light, speedvacuum > speedgas > speedliquid > speedsolid. See Figure 21.5 on page
356.
 All EM waves travel/move at about 3 × 108
푚
푠
in a vacuum. This is called the speed of light.
Don’t Read The Dual Nature of Waves and Particles on page 356.

21.2 The EM Spectrum
Classifying Waves
 Memorize Figure 21.7 on page 357. This is the EM spectrum. As you go from left to right in
the picture, the frequency of the wave increases, the energy of the wave increases, and the
wavelength of the wave decreases.
Speed, Wavelength, and Frequency
speed = wavelength × frequency = λ × f
 From the above equation if the speed of a wave is constant, as the λ ↓, f ↑. This is an inverse
relationship. Energy ∝ frequency so high frequency waves (like gamma rays) have greater
energy than lower frequency waves.
Radio Waves
 A radio wave has a length that can range from a football to a football field. It has the
longest wavelength and lowest energy in electromagnetic spectrum.
 Low energy radio waves are used by televisions, radios, and cellular phones.
Sending and Detecting Radio Waves
 An antenna oscillates/vibrates electric charges which creates an electromagnetic wave. This
antenna sends a radio wave. Another antenna detects the radio wave.
Microwaves
 Radio waves that have wavelengths between 1 mm (0.001 m) and 30 cm (0.3 m) are called
microwaves. Microwaves are used by microwave ovens to heat food by vibrating water.
Microwaves are also used by portable phones and cellular phones.
Radio Detecting and Ranging (Radar)
 Bats use echolocation to locate objects. Echolocation is the broadcast and reception of
sounds.
 Radio detecting and ranging, or radar, is echolocation that is used in technology. We use
radar to track/locate planes and weather fronts by using radio waves.
Infrared Waves
 The warmth from sunlight is from infrared waves. Infrared waves have wavelengths from
around 0.75 m to 0.001 m.
Infrared Subgroups
 There are three groups of infrared waves: near-infrared, mid-infrared, and far-infrared.
 Far-infrared have wavelengths that are close to microwaves. Sunlight is an example of far-infrared.
 Near-infrared have wavelengths that are close to visible light. Television remote controls
use near-infrared wavelengths.
Detecting Infrared Waves
 Some animals can detect/notice/sense infrared waves.
 Satellites use infrared waves to analyze/examine/study Earth’s surface.
Visible Light
 Visible light has wavelengths of about 0.0000004 m to 0.0000007 m.
 Each color has a different wavelength. See Figure 21.13 on page 360.
 When all the colors are present you get white light. The sun emits white light.
 Few objects emit light. Most objects reflect light.
 Plants use the red and blue wavelengths to create food by photosynthesis.
Ultraviolet Waves
 UV waves have enough energy to damage living cells and cause sunburn. See Figure 21.13
on page 360.

Beneficial Uses
 The human body uses UV energy to produce vitamin D.
 Hospitals use UV waves to disinfect equipment.
 Some materials emit visible light when struck/hit by UV waves. Police detectives use a
powder and UV light to look for fingerprints.
The Ozone Layer
 Ozone (O3) is found around 15 km above the Earth’s surface.
 Ozone absorbs (takes in) harmful/bad ultraviolet (UV) waves like x-rays and gamma rays
emitted by the sun. See Figure 21.14 on page 361.
 Ozone molecules are constantly being created/formed and destroyed by UV waves. This is a
natural process.
 Chlorofluorocarbons (CFCs) destroy the O3 in the ozone layer. This is an unnatural process.
X-Rays, Gamma Rays, and Their Uses
 X-rays have enough energy to pass through skin and muscle.
 The shortest wavelength and highest energy EM waves are gamma rays.
 X-rays are used to create images of the skeletal structure. See Figure 21.16 on page 362.
 Gamma rays are used to treat some cancers.
21.3 Producing Light
Types of Lighting
 Objects that give out (or emit) light are luminous. The sun is luminous.
 Objects that reflect light are illuminated. The moon is illuminated from the sun.
Incandescent Lights
 An incandescent light bulb produces light by heating a metal wire (which is usually
tungsten). Most of the energy, about 90%, is lost as heat. Only about 10% of the energy
produces light. See Figure 21.17 on page 363.
Fluorescent Lights
 A fluorescent light bulb is a glass cylinder. The glass cylinder is coated/covered with
phosphorus. Each end has an electrode. There is a low pressure gas inside the cylinder.
When a current (See chapter 23.) is turned on the two ends heat up and emit electrons. The
electrons hit the gas atoms in the tube. The gas atoms emit UV radiation. The phosphor
coating absorbs the UV waves and reemits the energy as visible light. See Figure 21.18 on
page 364.
 Fluorescent light bulbs are energy efficient. Unfortunately there is mercury inside the
cylinder.
Neon Lights
 Neon lights use a clear glass cylinder/tube with a gas inside. Neon gas produces red light.
Tungsten-Halogen Lights
 Tungsten-halogen lights are used when bright lights are needed.
 A halogen gas, usually fluorine or chlorine, is inside a quartz tube with a tungsten filament.
 Tungsten-halogen lights are used on movie sets, in underwater photography, and to light
airport runways.
Light Emitting Diodes (LEDs)
 An LED does not get hot and doesn’t have any filaments.
 An LED is an energy-efficient and long-lasting device/object. See Section 26.1

Light Amplification by Stimulated Emission of Radiation (Lasers)
 A laser is a device/object that produces a narrow/thin beam/ray of coherent light. Coherent
light waves all have the same frequency and travel/move with their crests and troughs
aligned/organized. Laser light has a high amount of energy in a small area because the light
does not spread out a lot when it travels. Laser light is not found in nature.
 All other light is incoherent. Incoherent light has a range of frequencies. Their crests and
troughs are not aligned. See Figure 21.21 on page 365.
 Lasers are used for cutting and welding objects, surveying and ranging, communication and
data transmission, and corrective eye surgery.
http://www.physicsforums.com/showthread.php?t=182755

Science Project Finds Plants Won't Grow Near Wi-Fi Router
http://www.liveleak.com/view?i=cd3_1369428648#eOOWMh7OQKxVwcsA.99
New study links over 7,000 cancer deaths to cell phone tower radiation exposures
http://www.naturalnews.com/040905_cell_phone_towers_radiation_cancer.html#ixzz2X3dmVqhJ
Shocking New Cell Phone Radiation Study Reveals Increased Brain Tumor Risk for Children
http://www.naturalnews.com/039419_cell_phone_radiation_brain_tumors_children.html#ixzz2NAA
ft4XR
Mobiles Can Give You a Tumour, Court Rules
http://www.thesun.co.uk/sol/homepage/news/4597109/Mobiles-can-give-you-a-tumour-court-rules.
html#ixzz2F6ycHfhY
Talented Musician Zapped to Death by Cell Phone Radiation
http://www.naturalnews.com/038395_cell_phone_radiation_electrosensitivity_fatality.html#ixzz2F
bsQwMcw
Electromagnetic radiation damages DNA, disrupts the blood-brain barrier, weakens and damages
sperm, and changes brain metabolism.
Research in Motion sells the smartphone with the warning, "Do not keep near the pregnant
abdomen."
http://hyperphysics.phy-astr.gsu.edu/hbase/emwav.html

Chapter 23 Electric Charges and Currents
23.1 What is Electric Charge?
Atoms and Electric Charge
 Electricity is the movement of e-.
 Atoms (like hydrogen, helium, lithium, copper, silver, and gold) are the basic building blocks
of matter. They are all made up of p+, e-, and n.
 An electrically neutral atom is an atom in which the number of p+ is equal to the number of
e-.
 An ion is an atom in which the number of p+ is not equal to the number of e-.
Electric 퐅 퐨퐫퐜퐞퐬
 Similarly charged objects/particles (like two e- or two p+) repel each other. Oppositely
charged objects/particles (like one e- and one p+) attract each other. (See Figure 23.3 on
page 393.)
 The electric f orce between two objects is
F⃑
electric =
kq1q2
r2 ,
where k is a constant, q1 and q2 are the net/total charges of the two objects, and r is the
distance between the two objects/particles. As the charge q1and/or q2 gets larger so does
the electric f orce between the two objects. As the distance r increases between the two
objects the electric f orce between the two objects decreases. This equation looks very
similar to the gravitational force between two objects in which
F⃑
gravitational =
Gm1m2
r2 .
 The electric f orce and gravitational f orce are both action at a distance f orces. They both
also exist in a vacuum.
Electric Fields
 The electric field creates/makes an electric f orce in the area around an electric charge. See
Figure 23.4 on page 394. Electric fields are perpendicular (90°) to the surface of the charged
object. The electric field is stronger if you put a “test charge” closer to the object and
weaker if you put a “test charge” farther away from the object.
 Electric field lines always point from a positive charge to a negative charge. The arrow
shows the direction in which a proton “test charge” would move.

http://www.physicsclassroom.com/class/estatics/u8l4c.cfm
23.2 Static Electricity
What is Static Electricity?
 Static electricity is the buildup of excess/extra charge on an object. This happens when the
number of p+ is not equal to the number of e- in an object.
 Electric discharge is the rapid/fast movement of e- from one place to another. See Figure
23.5 and 23.6 on page 395.
Charging Objects
 Conduction happens/occurs when e- move along the surface of an object and on to other
objects that are touching it.
 A conductor is an object in which e- move through it easily. Examples of conductors are H2O
and metals.
 An insulator is an object that holds e- tightly and keeps them from moving easily. Examples
of insulators are glass, air, plastic, rubber, and wood.
 Induction occurs when you charge a neutral object by bringing a charged object near it. See

Electric Discharges
 Electric discharge happens/occurs when an e- jumps from a negatively charged object to a
neutral or positively charged object.
 Lightning is produced/created when air currents separate charges inside a storm cloud.
 The negative charge in the storm cloud induces a positive charge in another storm cloud or
on the ground. When the charge difference is large enough the e- flow by lightning.
 Lighting can move from the cloud to the ground, from the ground to the cloud, or from one
cloud to another cloud. See Figure 23.10 on page 397.
 You can protect your house/property from lightning by installing a lightning rod. In a
lightning rod a metal pole is attached to a wire. A lightning rod lets electricity from lighting
reach the ground instead of a building or house.
 Safety Tip: When you see lightning stay away from high places, open areas, trees, and
conductors like metal fences/gates and water. Stay inside a building or hard topped car
since the conducting metals can redirect the lightning away from you.
http://ralphott.blogspot.com/2011/06/therapy-metaphors-lightning-rod.html
23.3 Making Electrons Flow
 Static discharge is not common enough to give electrical objects the energy they need to be
on for long periods of time. The solution is a current.
 I = 퐞퐥퐞퐜퐭퐫퐢퐜 퐜퐮퐫퐫퐞퐧퐭 =
Δ charge
Δ time
=
Δ q
Δ t
= [Amperes] = [A]. Current/I is when e- or ions
move through a conductor.
 Question: What is the difference between static electricity and electric current/I?
 Answer: Static electricity and electric current/I are the same thing but static electricity does
not happen/occur often while electric current flows regularly like water.
Creating a Current I
 An electric circuit is a closed loop/path of conductors through which current/I can
flow/move. If there is a break/gap in the circuit, current/I will not flow/move. See Figure
23.11 on page 398.
퐕퐨퐥퐭퐚퐠퐞 = potential difference that causes current/I to flow = [Volts] = [V]
 The voltage of a battery is similar to gravitational potential energy. Voltage is what causes
current/I to flow/move.

Class notes for pyp 001 semester 132 (3)

Class notes for pyp 001 semester 132 (3)

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