4. OBJECTIVES:
1. state Newton’s laws of motion.
2. explain how the mass of an object affects
inertia.
3. discuss the relationship of net force, mass
and acceleration.
4. give examples of the practical applications of
Newton’s law in daily activities
5. appreciate the application of Newton’s law of
motion in transport safety.
7. Newton’s First Law
Law of INERTIA
An object at rest tends to stay at
rest and an object in motion
tends to stay in motion unless
acted upon by an unbalanced
force.
10. What does this mean?
Basically, an object will “keep doing what it
was doing” unless acted on by an
unbalanced force.
If the object was sitting still, it will remain
stationary. If it was moving at a constant
velocity, it will keep moving.
It takes force to change the motion of an
object.
11. First Law: Law of Inertia
Inertia
Tendency of a body to stay at rest
when it is at rest or to stay in uniform
motion in a straight line unless acted
upon by an external force.
Qualitative in nature
Dependent on mass
13. Why was it so difficult
to stop the TITANIC from
colliding with the
iceberg?
14. The mass of
the Titanic is
very large.
Inertia is
proportionate
to mass.
The Titanic could not change
its direction because its
extremely high inertia forces
it to continue in a straight
line, thereby colliding with the
iceberg. men
u
16. SEATBELT LAW!!!
• REPUBLIC ACT NO. 8750
• an act requiring the
mandatory compliance
by MOTORISTS of private
and public vehicles to
USE SEAT BELT devices,
and requiring vehicle
manufacturers to install
SEAT BELT devices in all
their manufactured
vehicles
17. Think!
Why is it important for a
passenger vehicle driver not to
step on the break hardly when
the vehicle is fast moving?
18. First Law APPLICATION
• to dislodge ketchup
from the bottom of a
ketchup bottle, the
bottle is often turned
upside down, thrust
downward at a high
speed and then
abruptly halted.
19. First Law APPLICATION
• the head of a
hammer can be
tightened onto the
wooden handle by
banging the
bottom of the
handle against a
hard surface.
20. First Law: Law of Inertia
• =0
•a = 0
•Object is at rest
Fnet =0
• = constant
•a = 0
•Object moves at
the same speed
and direction
23. Newton’s Second Law
Law of ACCELERATION
The acceleration of an object is
directly proportional to the net
force acting on it and inversely
proportional to its mass.
25. 2nd Law: Law of Acceleration
ACCELERATION is directly proportional to
FORCE and inversely proportional to MASS.
The greater the FORCE, the greater
the ACCELERATION.
The greater the MASS, the greater the FORCE
needed for the same acceleration.
27. What does F = ma say?
Something very massive (high mass)
that’s changing speed very slowly (low
acceleration), like a glacier, can still
have great force.
Something very small (low mass)
that’s changing speed very quickly
(high acceleration), like a bullet, can
still have a great force. Something
very small changing speed very
slowly will have a very weak force.
34. 3rd Law
The reaction of a rocket is an
application of the third law
of motion.
The hot gases push against
the inside tube of the rocket
and escape out the bottom of
the tube. As the gases move
downward, the rocket moves
in the opposite direction.
35. 3rd Law of Motion
Flying gracefully
Reaction through the air, birds
depend on Newton’s
third law of motion. As
the birds push down on
the air with their wings,
the air pushes their
wings up and gives
Force them lift.
36. Summary:
Newton’s Laws of motion
a. Law of inertia
b. Law of acceleration
c. Law of action-reaction
37. AGREEMENT
1. Give situations that demonstrate Newton’s
Laws of Motion.
2. Research on the application of Newton’s
laws of motion in transport safety.
