Law of Inertia Law of Action and Reaction Law of Acceleration Law of Action and Reaction Law of Inertia

1. L E S S O N 4 : H O W D O O B J E C T S M O V E ?
L E S S O N 5 : H O W D O N E W T O N ’ S L A W S O F M O T I O N E X P L A I N T H E M O T I O N O F A N
O B J E C T ?
L E S S O N 6 : W H A T I S N E W T O N ’ S L A W O F U N I V E R S A L G R A V I T A T I O N ?
L E S S O N 7 : H O W A R E M O M E N T U M A N D E N E R G Y C O N S E R V E D ?
UNIVERSAL LAWS OF
PHYSICS

2. LESSON 5:
HOW DO OBJECTS
MOVE?

3. DEPARTMENT OF EDUCATION
SCIENCE CROSS-SPECIALIZATION
FORCE, MOTION AND ENERGY
Teaching and Learning Division
DESCRIBE THE MOTION OF THE GIVEN
BODIES
What would be a good frame of reference to use
when describing the car’s motion? The driver’s
motion?
1 3
2
4-5

4. DEPARTMENT OF EDUCATION
SCIENCE CROSS-SPECIALIZATION
FORCE, MOTION AND ENERGY
Teaching and Learning Division
Describe the motion of the given bodies
Figure 1Reference Points The
passenger can use a tree as a reference
point to decide if the train is moving. A
tree makes a good reference point
because it is stationary from the
passenger’s point of view.
6
7

5. What is Motion?
The change in position with respect to a reference
point
Objects that we call stationary—such as a tree,
a sign, or a building—make good reference
points.
A reference point is a place or object used for
comparison to determine if something is in motion.
An object is in motion if it changes
position relative to a reference point.

6. DISTANCE AND DISPLACEMENT
• Distance – refers to the total path length
traveled between two points.
-It is a SCALAR quantity that has
magnitude but with no direction.
• Displacement - refers to the change in position
of a body relative to some reference point.
I - it is a VECTOR quantity that
has both magnitude and direction.

7. QUICK CHECK
Identify the physical properties
described by the following:
•3. 350 km
•4.120 km, S
•5. 510 m
•40 m, NW
•100 km, E

8. SPEED AND VELOCITY
• Speed – is the rate of motion.
Average speed is the total distance an object travels
divided by the time it takes to travel that distance.
average speed =
𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑒𝑑
𝑡𝑖𝑚𝑒 𝑜𝑓 𝑡𝑟𝑎𝑣𝑒𝑙
Instantaneous Speed - tells how fast the car is moving
at a given instant.
Speedometer – is a device that measures instantaneous
speed.
Uniform motion – an object moving at a constant speed
in a single direction.

9. SPEED

10. QUICK THINKING
1. Johnson covers a distance of 1.5 km in 10
minutes to reach turret. What is the average
speed in m/s?
2. Lesley walks a distance of 300 m with an
average speed of 1.5 m/s. What time is
required to walk this distance?

11. SPEED AND VELOCITY
• Velocity – refers to the speed of an object in a particular
direction.
• Instantaneous Velocity – the instantaneous speed at a
given instant in time and having direction corresponding
to that of an object in a particular direction.
• Average velocity – is the change in displacement divided
by the time interval required for the change.
average velocity=
𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑑𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡
𝑒𝑙𝑎𝑝𝑠𝑒𝑑 𝑡𝑖𝑚𝑒

13. ACCELERATION
• ACCELERATION refers to the change in velocity of a
moving object per unit of time.
• In change in velocity can be achieved in three ways:
1. By increasing its speed while traveling in a straight line
2. By decreasing its speed while traveling in a straight line
3. By changing its direction even while traveling at a constant
speed
acceleration=
𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦
𝑒𝑙𝑎𝑝𝑠𝑒𝑑 𝑡𝑖𝑚𝑒
acceleration=
𝑓𝑖𝑛𝑎𝑙 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 −𝑖𝑛𝑖𝑡𝑖𝑎𝑙 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦
𝑒𝑙𝑎𝑝𝑠𝑒𝑑 𝑡𝑖𝑚𝑒

14. ACCELERATION
1. A car starts from rest and accelerates at a constant rate
of 2.5 m/𝑠2 for 5 s. What is the velocity of the car after 5
s?
2. A roller coaster is moving up at 25 m/s from the bottom
of the hill. It decelerates at the rate of 6 m/𝑠2 at the top
of the hill. How long did the roller coaster decelerates?

15. ACTIVITY
1. A boy swims from one end of a 30-m long pol to the other end
and returns to his starting point in 28 s. What is his average
speed?
2. A man is planning a trip between two cities and finds the total
distance to be 585 km. He thinks that he will be able to make a
trip at an average speed of 80 km/h. how long will be the
amount of time he should allow for the trip?
3. A car on a straight road starts from rest and accelerates
uniformly until it reaches 30m/s in 10 s. What is the acceleration
of the car during this time?
4. A truck moving with an initial velocity of 25m/s slows down at a
constant rate of 4 m/𝑠2. What is its velocity after 3 s of
deceleration?

16. LESSON 6:
HOW DO NEWTON’S
LAWS OF MOTION
EXPLAIN THE MOTION OF
AN OBJECT?

17. MOTION ACCORDING TO ARISTOTLE
AND GALILEO
ARISTOTLE GALILEO
VERTICAL MOTION • Any object not in its
natural place will strive
to get there.
• Object fall at a rate
proportional to their
weight.
• Any two objects that
are dropped together
will fall together
regardless of their
weight if air resistance
is negligible.
• Objects fall at the
same rate
HORIZONTAL MOTION • Force is needed to
start and sustain the
motion of an object
• Force is not needed to
sustain motion of an
object.
• Force is required to
change motion (to
accelerate)

18. MOTION ACCORDING TO ARISTOTLE
AND GALILEO
ARISTOTLE GALILEO
PROJECTILE MOTION • A force is needed to
start an object to move
through air until its
natural motion
eventually brings it to
Earth.
• A projectile is
influenced by vertical
motion due to the
force of gravity and
horizontal motion that
is uniform.

19. NEWTON’S LAWS OF MOTION
Isaac Newton – made a systematic study of
motion and extended the ideas of Galileo by
formulating the three laws of motion.
1. Law of Inertia
2. Law of Acceleration
3. Law of Interaction

20. LAW OF INERTIA
• States that, “ an object remains at rest, or in uniform
motion in a straight line, unless acted on by an
external unbalanced force.”

21. LAW OF INERTIA
• Unless acted
upon by an
unbalanced
force, this golf
ball would sit
on the tee
forever.

22. LAW OF INERTIA
• MASS is the measure of the amount of matter
in an object. It is measured in Kilograms (kg)
• INERTIA is a property of an object that
describes how much it will resist change to the
motion of the object.
• More mass means more inertia

23. LAW OF ACCELERATION
• “The acceleration of an object is directly
proportional to the magnitude of the net
force acting on it and is inversely
proportional to its mass.”
acceleration = 𝐹𝑜𝑟𝑐𝑒
𝑚𝑎𝑠𝑠

24. LAW OF ACCELERATION

25. LAW OF ACCELERATION
Suppose a ball of mass
0.60 kg is hit with a force
of 12 N. Its acceleration
will be:

26. LAW OF INTERACTION
“For every action, there is an
equal and opposite reaction.”

27. LAW OF INTERACTION
“For every action, there is an
equal and opposite reaction.”

28. QUICK CHECK
What law of motion is illustrated in the following.
1. When a dog finishes swimming, it shakes itself
to dry.
2. A ball bounces.
3. A truck has a more powerful engine than a
small car.
4. A fireman using a fire hose holds it tightly.
5. A person jumping out of a moving vehicle runs
a few steps before coming to rest.