Unit c heattemperaturenotes

1. Unit C
Heat & Temperature

2. What is Heat?
After experimentation in the 1600's, a caloric theory was
developed
Caloric: a self-repellent fluid that flows from hotter
bodies to colder bodies
What is the problem?
Heat does not change the mass of an object

3. What is Heat?
Heat is not a substance
Heat: a form of energy that flows from hot (more
energy) to cold (less energy)

4. Kinetic & Thermal Energy
Kinetic Energy: energy of movement (specifically
movement of particles)

5. Kinetic & Thermal Energy
Thermal Energy: total kinetic energy of the particles in a
substance (Total Kinetic energy)
The soup in the bowl and the soup in the spoon have the
same temperature (same average KE.) BUT the bowl has more
thermal energy

6. What is Temperature?
Temperature: The measurement of how hot or cold
something is. (The average kinetic energy of the
particles)

7. What is Temperature?
Handy Thermometer

8. What is Temperature?
Answer these on your lined paper
1. What do you think the temperature of each
bucket is?
2. What happened when you switched your hands
from the ice one and hot one?

9. What is Temperature?
What makes a good thermometer?
• Reliable
• Consistent
• Accurate
• Readable
• Etc.
Thermometer: An instrument for measuring
temperature (Accurately)

10. Heating Technology

11. Heating Technology
Furnaces and Air conditioners are examples
of technologies we use.

12. Heating Technology Timeline
7000 BC or earlier:
Humans Created Fire
100 BC: Romans
developed central heating
(heat travels from 1
source to different areas
in a building)

13. Heating Technology Timeline
1200: Chimneys first
appear in Europe
1300: Fireplaces with
chimneys are built into
the walls of buildings

14. Heating Technology Timeline
1700s: Cast-iron stoves
are used to heat rooms
Late 1700s: Central
Heating reappears using
coal

15. Heating Technology Timeline
1800s: forced-air heating
1906: Electric heaters

16. Needs vs Wants
Needs: are things we must have to stay alive (food, water, air)
Wants: are things we would like to have (I-pods, cell phones,
TV’s)
In Canada we have some heat technology NEEDS.

17. Needs vs Wants
Standard of Living: A measure of how well
we live, including the level of technology that
we use in our daily lives

18. Heating Technology Timeline
Think about
microwaves!
What others can you
think of?

19. Controlling Heat
Why do we need to control heat?
Example: A furnace and a thermostat.
A furnace generates and transfers the heat from one area to
another.
A thermostat allows us to control and monitor that heat. If
it is too hot, we turn the thermostat down. If it is too cold,
we turn the thermostat up.

20. Sustainable
vs
Non-Sustainable

21. Sustainable
Sustainable: means something can be maintained or
used again and again
Examples of Sustainable Resources:
• Wind
• Water
• Wood

22. Non-Sustainable
Non-Sustainable: means something can NOT be
maintained or used again and again
Examples of Non-Sustainable Resources:
• Coal
• Oil
• Gas

23. Sustainable or Non-Sustainable
What about the sun?

24. Particle Model of
Matter (PMOM)

25. What is matter?
• Matter: The stuff that makes up the universe that is
not energy
• Matter:
1. Has mass
2. Takes up space

26. States of Matter
States of Matter: distinct forms in which matter can
exist.
Bose-Einstein
Condensate
5

27. States of Matter
To move between states the matter must gain or lose
heat energy
Bose-Einstein
Condensate
5

28. The Particle Model of Matter (PMOM)
1. All matter is made of tiny particles
2. Particles are in constant motion
3. Adding heat to matter makes the particles move faster
4. There are attractive & repulsive forces between particles
5. There are spaces between the particles
6. (Different matter is made of different particles)

30. Solid
Solid:
• Particles are very close together
• Definite shape and volume
(Volume: the amount of space the matter occupies)

31. Liquid
Liquid:
• Particles are loosely attached to each other
• Take the shape of its container
• Has definite volume

32. Gas
Gas:
• Particles are not connected
• Has no definite shape
• Has no definite volume

33. Solid Liquid Gas
Motion of
Particles
Space between
particles
Behaviour in a
container
LOW Medium HIGH
Not affected
by the
container
Takes shape
of the
container
Fills the
container

35. Changing Between
States of Matter

36. The Effect of Heat
Heating particles adds energy to them. This energy is
in the form of movement. We call this kinetic energy.
Therefore, to change the state of matter, you
must change its kinetic energy.
When particles gain kinetic energy (heat) they
move faster. Because of this, they take up more space.

37. The Effect of Heat
Phase Change: When matter goes from one state (solid,
liquid, gas) to another.

39. Melting: Going from a solid to a liquid when heat is added

40. Boiling: Going from a liquid to a gas when heat is added

41. Condensation: Going from a gas to a liquid when heat is
removed

42. Freezing: Going from a liquid to a solid when heat is removed

43. Sublimation: Going from a solid to a gas when heat is added

44. Deposition: Going from a gas to a solid when heat is removed

45. Changes Between States of Matter
Melting: Going from a solid to a liquid when heat is added
Boiling: Going from a liquid to a gas when heat is added
Condensation: Going from a gas to a liquid when heat is
removed
Freezing: Going from a liquid to a solid when heat is removed
Sublimation: Going from a solid to a gas when heat is added
Deposition: Going from a gas to a solid when heat is removed

46. How Heat Affects
Volume

47. How Heat Affects Volume
• Volume: How much space something takes up
• The volume of matter can be changed with heat energy.
• Adding energy -> particles move faster -> have more collisions -> take up
more space.
• Losing energy -> particles slow down -> have less collisions -> take up less
space.

48. How Heat Affects Volume
• Therefore: the more collisions, the more space that is required!

49. How does that explain how a hot air balloon works?

50. Expansion vs Contraction
• Expansion: Becoming larger due to the
addition of heat
• Contraction: Becoming smaller due to losing
heat

51. Expansion vs Contraction
• Adding thermal energy to a solid
will increase its volume.
• So...
• When a solid heats up it expands.
(exits away)
• When a solid cools down it
contracts. (comes together)

52. Expansion vs Contraction
• Liquids: Look at a thermometer. The
liquid expands when it gets warm and
contracts when it gets cold.
• Gases: Think of a helium balloon, once
it cools down, it begins to fall closer to
the group and the balloon looks
smaller.

53. Expansion vs Contraction
• There is an Exception!
• Can you think of one substance that expands as it get colder?

54. Expansion vs Contraction
• H2O or water is one of the only
substances that the solid form
has a greater volume than
the liquid form.
• This is why Ice floats and we get
potholes!

55. Conduction

56. What is better for cooking?
• Metal or Wood?
• The wood spoon would be better, because the metal spoon could get hot and burn
you!
• This means that metal conducts heat better than wood.
Heat Heat

57. Conduction
• Conduction: the transfer of heat energy between
substances that are in contact

58. Conduction
• This happens like a chain reaction. The heat travels from particle to
particle, through the substance. Even a solid

59. Conduction
• Conductors: Materials that allow for
easy transfer of heat
• Insulators: Materials that do not
transfer heat easily
Insulators are essential when dealing
with large amounts of heat

60. Conduction
Name some insulators you see every day!
• Wood,
• Rubber (Cooking tools, hot water bottle)
• House
• Clothing
• Plastic
• Thermos

61. Convection

62. Convection
• Convection: Heat travelling through gases and liquids since they flow.
Heat is transported by the motion of particles.
• Hot particles rise up through the substance, and cooler particles move
in to take their place near their bottom.

63. Convection

64. Convection
• Convection Current: The
circular pattern caused by the
moving particles during
convection.
• The heat moves from high-
energy to low-energy

65. Radiation

66. Radiation
• Radiation: Transfers heat through infrared
waves (same as light waves)
• Radiation is the only energy transfer that does
not rely on particle movement
• Radiant Energy: Energy carried through
radiation

67. Radiation
• What is our greatest source of radiant energy?
• THE SUN
• Heat from the sun cannot reach us by conduction or convection

68. Radiation
• The texture and color of objects can
affect how well they absorb radiation
• Dark materials absorb radiation better
than light materials
• Rough/dull textures absorb radiation
better than smooth or shiny materials
• Think of Foil!

69. All 3 Types of Heat Transfer

70. Natural Ways to
Produce
Thermal Energy

71. Natural Ways to Produce Thermal Energy
• Sun
• Radiant energy heats the surface
of the earth
• Geothermal Energy
• It’s very hot deep inside of the Earth and it’s
possible to obtain some of this energy

72. Natural Ways to Produce Thermal Energy
• Fire
• Fire Convert chemical energy into
thermal energy
• Decay
• When organic material decays, it lets off heat

73. Natural Ways to Produce Thermal Energy
• Solar energy is the most simple
natural resources to harvest. Many
homes are now being built with
active or passive solar heating.
• But experts disagree as to whether
or not solar energy is enough to fuel
our demands.

74. Passive vs Active
Heating

75. Passive Solar Heating
• "Reduce heat loss and increase heat gain from
the sun."
• Uses materials in the structure to absorb, store,
and release solar energy. Examples: insulating as
much as possible, having large south-facing
windows, putting deciduous trees in front of
windows to reduce heat gain in the summer but
allow heat gain in the winter.

76. Active Solar Heating
• Uses mechanical devices to
distribute stored thermal energy.
Has three components: a
collector, a heat storage unit, and
a heat distribution system.

77. Solar Energy
• https://www.youtube.com/watch?v
=4uPVZUTLAvA

78. Heating Systems

79. Thermostats
• "Thermo" = heat "stat" = maintain or keep the
same
• In order to control or regulate the temperature of
a room or house, we need a thermostat.

80. Thermostats
• When heated, one metal expands
faster than the other, causing it to
bend.
• The bending is used to measure
temperature change.
• When the strip bends/unbends,
it opens/closes an electric circuit
that controls the device.

81. Bimetallic Strip

82. Local vs Central Heating Systems
• Thermostats can control two different heating systems:
• Local Heating System Central Heating System

83. Local Heating Systems
• -Provide heat for one room or
small area.
• -Relies on convection to
transport the heat.
• -Ex. Fireplaces, wood-
burning stoves, space heaters,
etc

84. Central Heating Systems
• -Heat is gathered in one area, then
transported throughout the
building/system.
• -Transfer is through vents, pipes,
ducts, etc.
• - Two kinds of central heating
systems are through forced-air
heating or hot-water heating.

85. Forced Air Heating
• Air is heated in a furnace.
• Air travels through ducts and into
other rooms.
• Convection transports heat once
it exits ducts

86. Hot Water Heating
• Water is heated in a furnace/boiler.
• Pumps push water through radiators
in the house.
• Hot air travels from the radiator
through convection.
• Cold water returns to the boiler.

87. Heating Efficiency

88. Insulation
• Controlling indoor temperature is very
important in Alberta. In the winter, it's
important to keep the hot air inside.
During the summer, you would like to
keep the warm air outside. This is
achieved with insulation!
• Insulators Reduce Heat Transfer

89. Insulation
• Some objects are better insulators
than others.
• The insulating property of an object
is called the thermal conductivity,
and this is recorded as the R-Value.
The higher the R-Value, the better
the insulation.

90. Insulation
• Brick walls, styrofoam and fiberglass are examples of good insulators.
• Doors and windows can be designed to be good insulators.

91. Where is most heat lost in a home?

92. Efficiency
• Efficiency: How well a device uses the energy that goes into it. If energy is
made that isn't useful for the desired job then it is inefficient

93. Efficiency

94. Sources of Heat

95. Renewable vs. Non-renewable
• Renewable: Natural
resources that can be
replaced.
• Non-renewable:
Resources that cannot
be replaced.

96. Fossil Fuels
• Fossil Fuels:
• Non-renewable
• Source of almost all of the world's
heating/electricity.
• Made from remains of plants and animals
that died millions of years ago.

97. Fossil Fuels
• Economic Cost: Cost to obtain fuel. Cost
increases as supplies decrease.
• Environmental Cost: Effect on environment.
Main effect is air pollution.
• Societal Cost: Effect on people. Air pollution
leads to health risks, increases medical costs...

98. Alternatives to Fossil Fuels
• Wind Energy:
• -Captured by windmills
• -Inexpensive and simple
• -Only works in windy regions

99. Alternatives to Fossil Fuels
• Nuclear Energy:
• -Uses uranium to make heat
• -Takes only a small amount of fuel
• -Non-renewable
• -Waste is very harmful (radioactive waste
takes 100's or 1000's of years to disappear)

100. Alternatives to Fossil Fuels
• Hydro-Electric:
• -Captured energy of falling water
• -Clean and renewable
• -Expensive to build

101. Alternatives to Fossil Fuels
• Cogeneration:
• -Waste heat energy is recycled to
produce steam.
• - Expensive