science1 q2 module3 l1 2_3

1. INTEGRATED SCIENCE
Quarter 2: Force, Motion and Energy
Module 3: The Laws of Motion
You will study the following topics in this module:
Lesson 1: Description of Motion
Lesson 2: Causes of Motion
Lesson 3: Forces and Equilibrium
EXPLORE Your Understanding
You will be given an overview of the laws of motion. Your knowledge on motion
concepts gained from elementary science and concepts related to it will be diagnosed.
Pre-Assessment
Directions: Choose the letter of the correct answer. Write your answers on a separate
sheet.
1. How do you measure the distance between two points?
a. by getting the time c. by getting the length
b. by getting the weight d. None of these
2. Which of these devices measure time interval accurately?
a. stopwatch b. wristwatch c. clock d. All of these
3. Speed is
a. measure of how fast something is moving.
b. the distance covered per unit time.
c. always measured in terms of a unit of distance divided by a unit of time.
d. All of the above
4. Unless stated otherwise, when we discuss the speeds of things, we mean with
respect to the center of the universe.
a. True b. False
5. Acceleration is defined as the CHANGE in
a. velocity of an object.
b. velocity divided by the time of travel.
c. distance divided by the time of travel.
d. time it takes to move from one speed to another speed.

2. 6. Inertia is a measure of an object’s
a. weight. b. velocity c. mass. d. gravity
7. Whenever an object exerts a force on another object, the second object exerts a
force of the same magnitude, but in opposite direction to that of the first object.
a. Always true c. Always false
b. Sometimes true . d. Sometimes false
8. Newton’s Second Law says that the
a. force on an object equals the product of its mass times its acceleration.
b. acceleration of an object equals the product of the force on it times its mass.
c. mass of an object equals the product of the force on it times its acceleration.
d. force on an object equals its acceleration divided by its mass.
9. Friction is a force that always acts
a. opposite to the object’s motions.
b. in the same direction as the object’s motion.
c. perpendicular to the object’s motion.
d. vertically to the object’s motion.
10. If the force of gravity suddenly stopped acting on the planets, they would
a. continue to orbit the sun.
b. fly straight away from the sun.
c. move in a straight line tangent to their orbit.
d. spiral slowly away from the sun.
KWL Chart
Before you begin with the next part of this module, fill in the first two columns. Fill in the
last column after completing the module.
Laws of Motion
What I learn What I know What I will learn

3. Your understanding of laws of motion will be increased as you study the lessons and
perform the activities in the FIRM UP phase.
FIRM Up Your Understanding
In this phase, varied learning experiences shall be introduced to help you understand
laws of motion and equip you with skills and knowledge for you to be successful
throughout the topic.
Lesson 1: Description of Motion
A. How are things moving?
1. Distance, Displacement, Speed and Velocity
The way you perceive motion depends on your location and whether you are in
motion. You need to compare the location of the object with the location ofanother
object, i.e. you need a reference point. The measure on how quickly an object
changes position is the speed of the object. By giving the direction makes the
description more accurate, hence you arrive at the displacement and velocity of
the object.
Activity 1: Estimating Average Speed
Determine your time of travel for 20 meter distance.
Time of Travel Average Speed
Walking
Jogging
Jumping
Motion – change in position with respect to a fixed point.
Relative Motion – a body is considered to have movement as long as it changes
its position from a given fixed point. However, using another
fixedpoint/s may not have changed the body’s position.
Distance – a measure of length without regard to direction.
Displacement – change in position with respect to a fixed point (direction of
motion is indicated).
Speed – distance covered per amount of travel time and does not include
direction of motion.
Velocity – distance covered per amount of travel time and includes direction of
motion.

4. 2. Uniform Velocity and Uniform Acceleration
Activity 2: Try to jog by covering the same distance for the same time interval
along one direction. This is uniform velocity. In observing another
moving event, the speed of a falling ball changing proportionately
with time is uniform acceleration.
Consider the following data:
Uniform Velocity Uniform Acceleration
d (m) t (s) v (m/s) d (m) t (s) v (m/s) a (m/s/s)
1 1 1 1 1 1 1
2 2 2 2 2 2 1
3 3 3 3 3 3 1
4 4 4 4 4 4 1
where vi = 0, d = vt, a = vf/t
Answer the following questions:
1. What is the acceleration of the body moving with uniform velocity?
2. Describe the change in velocity per second of a body with uniform
acceleration.
3. Free Fall, Projectile, and Circular Motion
A. Free Fall Motion
Release a small stone from the hand and get its time of fall.
Repeat releasing a bigger stone from the same height and get again its
time of fall.
Free fall is a vertical motion going downwards, or it accelerates towards the
surface of the earth.
A ball thrown straight up is opposite the direction of free fall. Neglecting air
resistance, a freely falling body is uniformly accelerating towards the earth.
B. Projectile Motion
Toss two coins on top of the table simultaneously dropping one and the
other coin moving horizontally while it is going down.

5. Projectile motion is a two-dimensional motion. It is easier to understand this
if the complete motion is split into two. The first goes horizontally and the
second moves vertically. Ignoring air resistance, the body accelerates
vertically downwards and moves horizontally with uniform velocity.
C. Circular Motion
Draw a circle on the floor where one can walk uniformly and show his
direction as he goes around it.
Circular motion moves the body in a circular path. It is similar to a
horizontal projectile except that it completes its curve into a circle. The
direction of the velocity is tangent to the circular path.
Lesson 2. Causes of Motion
A. Why do objects move?
Answer the following questions:
1. What cause/s uniform speed or uniform velocity and uniform acceleration?
2. What cause/s projectile motion?
3. What cause/s circular motion?
Activity 1: Inertia at Rest
Pull a coin atop a card on top of a drinking glass and observe.
Object at rest, like the coin in the activity, tends to remain at rest as the
card is removed and hence, it dropped to the drinking glass and not carried
by the card.
1. Law of Inertia – Every object continues in its state of rest, or in uniform speed in a
straight line, unless acted on by a nonzero force.
Activity 2: Law of Acceleration
A. Tie a string to a toy car and pull it gently. Using the same setup, pull the toy car
with a greater force.
Which moves faster, the car pulled gently or the car pulled with the greater force?
Why?
B. Pull the toy car gently and then pull it again gently with a stone on it.
Which moves easier, the car without the stone or with the stone? Why?

6. Motion is described by how fast it moved and depends on two quantities; the
amount of force you exert and the amount material the object contains.
2. Law of Acceleration – The acceleration produced by a net force on an object is
directly proportional to the net force; is in the same
direction as the net force, and inversely proportional to the
mass of the object.
Activity 3: Action and Reaction Forces
Connect two spring balances (force measurers) and pull them on opposite
direction similar to a tug-of-war. Compare the readings on each spring balance.
Newton’s third law relates action and reaction forces, i.e. forces always come in
pairs. Every time an object exerts a force on another object, the second object
exerts a force that is equal in size and opposite in direction back on the first
object.
3. Law of Interaction – forces come in pairs referred to as the action-reaction forces.
These forces are equal in magnitude and opposite in
direction.
4. Momentum and Law of Interaction
Activity 4: Impulse and Momentum
Try catching a fast ball without gloves?
Observe.
How will you catch the same ball with bare hands without being hurt?
Catching a ball involves overcoming the ball’s speed and mass which constitute
the momentum (p = mv) of the ball. The greater the speed or the mass of the
ball, the greater its momentum.
A change in momentum will result to a change in force. The larger the change in
momentum will give rise to a large change in the force and a bigger acceleration
that will result to possible crashes or collisions. This idea of from the Second
Law of Motion helps us infer how to be careful and prevent accidents.
F = ma, F = m(v/t), but p = mv,
hence F = p/t, and p = Ft or Ft = mv
When a ball is caught, we know that the ball has momentum directed towards the
catcher; at the same time the catcher has an equal momentum towards the ball.

7. From the Law of Interaction, equal and opposite forces create opposite
accelerations such that momentum before the interaction (collision) is also equal
and opposite the momentum after the interaction (collision).
What is this telling you about the speed of the ball and its mass compared to the
speed of the catcher and his mass?
As a consequence of Newton’s Law of Interaction, the momentum before
collision is equal to the momentum after collision which is another way of stating
the Law of Conservation of Momentum.
5. Law of Universal Gravitation
Why do you think the planets in the our solar system remain in their orbits as
they move around the sun?
This attraction of all objects in the universe is controlled by the Law of Universal
Gravitation. For as long as there are masses involved, the law applies.
Lesson 3. Forces and Equilibrium
1. Mass, Weight and Gravity
Mass – is a measure of inertia or the amount of matter an object has.
Activity 1: Mass and Inertia
Release two balls of different sizes from the second floor of the building and
determine which ball will hit the ground first. (If you have difficulty seeing which
ball hits first, listen to the sound produced by the balls hitting the ground.)
Explain your observation.
Activity 2: Weight and Gravity
Materials: pencil, paper cup, water, basin
Procedure :
1. Carefully use the pencil to punch a hole that is the width of the pencil in the side
of the cup, about one-third of the way up from the bottom.
2. Holding your finger over the hole, fill the cup three-fourths full of water.
3. Hold the cup above the basin. Predict what will happen if you remove your
finger from the hole. Remove your finger and observe what happens.

8. 4. With your finger over the hole, refill the cup to the same level as in Step 2.
Predict how the water will move if you hold the cup 50 cm above the dishpan
and drop the cup and its contents straight down to the pan.
What do you think?
(1) What happened to the water in step 3? in step 5?
(2) How did gravity affect the water when you dropped the cup?
Weight – describes the force of gravity acting on an object or the gravitational
force with which bodies attract each other.
Gravity – the force of attraction between two masses. Earth’s gravity is pulling
people to the ground. The strength of the gravitational force between two
objects depends on their masses. Example, the pull between you and the earth
is much greater than the pull between you and a book.
2. Friction – It is a force that resists motion between two surfaces that are
pressed together. It slows down the motion of objects.
3. Equilibrium – This is the condition when the net force acting on an object is
zero and the forces on the object are balanced.
Equilibrium and the law of acceleration help us prove the existence of forces that
are difficult to see. An example is a book at rest on a table. This means the book
has zero acceleration and thus has zero net force. But we know there is weight,
so there must be another force in the opposite direction that makes the net force
zero (normal force).
This means emphasis must be shown on how forces act in equilibrium – maybe
forces are balanced rather than zero force acting on an object which is the basis
for the use of product standards in buying monobloc chairs, banca, bridge,
signboard, computer table, etc. Although balanced forces have the same effect
as no force at all, the motion does not change at all. It is either at rest or moving
with constant velocity. Hence, fixtures requiring steady motions or always at
stationary must have balanced forces.
After firming up your understanding on scientific method, you have to deepen
your understanding by doing the following activities.

9. DEEPEN Your Understanding
Here, you shall be engaged in understanding scientific knowledge which includes the
processing and making meanings out of the information. You need to reflect, revisit,
revise and rethink your ideas; express you understandings and engage in meaningful
self-evaluation; and undergo in-depth exploration of the laws of motion and related
concepts.
Activity 1: Laws of Motion and Safety
Cite ways on how laws of motion can be useful in life.
Assess whether the laws of motion can help one become safety conscious.
Activity 2: Importance of the Laws of Motion
Contemplate and enumerate five (5) answers to the question, “In what way are
the laws of motion important in daily life?”
Summative Evaluation
1. A position describes an object’s location compared to
a. its motion. c. its speed.
b. a reference point. d. a vector.
2. Maria walked 2 km in half an hour. What was her average speed during her walk?
a. 1 km/h c. 4 km/h
b. 2 km/h d. 6 km/h
3. You kick a ball on a level sidewalk. It rolls to a stop because
a. there is no force on the ball.
b. gravity slows the ball down.
c. air pressure is pushing down on the ball.
d. friction slows the ball down.
4. Newton’s second law of motion states that to increase acceleration, you
a. increase force. c. increase mass.
b. decrease force. d. increase inertia.
5. A wagon is pulled down a hill with a constant velocity. All the forces on the wagon
are
a. balanced. c. increasing.
b. unbalanced. d. decreasing.
6. An action force and its reaction force are

10. a. equal in size and direction. c. different in size but in the same direction.
b. equal in size and opposite in direction. d. different in size and in direction.
7. John pulls a box with a force of 4 N, and Jason pulls the box from the opposite side
with a force of 3 N. Ignore friction. Which of the following statements is true?
a. The box moves toward John. c. The box does not move.
b. The box moves toward Jason. d. There is not enough information to
determine if the box moves.
8. You push a chair at a constant velocity using a force of 5 N to overcome friction. You
stop to rest, then push again. To start the chair moving again, you must use a force
that is
a. greater than 5 N. c. greater than 0 N but less than 5 N.
b. equal to 5 N. d. 0 N.
9. A rock is thrown vertically into the air. At the very top of its trajectory the net force on
it is .
a. less than its weight. c. its weight
b. more than its weight. d. zero
10. A truck and a car traveling at the same speed have a head-on collision. The vehicle
that will have greater damage is the
a. car. b. truck. c. both will have the same damage.
Now that you have gained a better understanding on scientific processes and methods,
you are now ready to for the next level- transferring what you have learned.
TRANSFER Your Understanding
This part will let you transfer your learning in new settings and use this creatively to
generate new ideas, view things differently and reengineer processes. You shall be
involved in designing, constructing, planning, producing new knowledge and/or
inventing products which can contribute to the safety and protection of people from
accidents.
Activity: Laws and Motion and Safety Rules

11. Prepare safety rules and protection at home, school or community integrating the laws
of motion and evaluate.
Resources (Web sites, Software, etc.)
Hewitt, Paul G. et al. 1994 Conceptual Physical Science. Harper Collins
College Publishers: New York
Littell, McDougal. 2005. Science. Integrated Course I. Evanston, IL.Houghton
Mifflin Company
`
Answer Key
Pre-Assessment: 1.c, 2.d, 3.d, 4.a, 5.d, 6.c, 7.a, 8.a, 9.a, 10.c
Summative Evaluation: 1.b, 2.c, 3.d, 4.a, 5.a, 6.b, 7.a, 8.a, 9.c, 10.a