MOMENTUM & IMPULSE
GRADE 9 PHYSICS
Dear God,
We thank You for the school that we
have.
We pray to You that this may serve
as a safe place for all of us to learn,
have fun, and build strong
friendships.
Thank you to the teachers who teach
us.
Thank you for the friends – the
people we can learn new things with.
And thank you for the beautiful day
you give us to learn, to serve others,
and to remember the Truth of Your
Glory!
In Jesus’ name. Amen
Tell Me
Learning Objectives:
1. Define impulse and momentum of an object
2. Identify the factors that affect the momentum of
an object
3. Relate impulse and momentum to collision of
objects
4. Apply the impulse-momentum theorem to a
variety of real-world problems
MOST ESSENTIAL
21
LEARNING COMPETENCY
Relate impulse and momentum to
collision of objects (e.g., vehicular
collision) (S9FE-IVb-36)
GUESS WHAT ?
Guess the word to
be formed by doing
addition or subtraction
from the given pictures
and letters
MASS
The property of a body that is a measure of
the amount of material it contains and causes
it to have weight in a gravitational field.
-P+
- GRA
SPEED
The rate of motion; act or
state of moving
- ADS +
-D
VELOCITY
The rate of change of
position along a straight
line with respect to time
- AS + LO +
ACCELERATION
The rate of change of
position along a straight
line with respect to time
- SK +
-L
-N
FORCE
Cause of motion; physical
strength or power
-U+
- VI
Activity 1:
What affects motion/momentum?
Directions: Study and analyze the pictures below.
Answer the given questions carefully.
YOU CAN’T STOP ME!
If the two vehicles suddenly
lose their breaks and crash
against the wall,
a. which do you think would be
more damaging?
b. on what factor would the
impact of collision depend if
their velocities are the same?
Figure 1. (Two vehicles of different masses are
moving at the same velocity)
Figure 2. (Two identical cars of different
velocities)
a. Which of the two cars would be more difficult to
stop?
MOMENTUM
What is Momentum?
MOMENTUM is a moving object’s tendency to
resist any change in it’s state of motion; inertia
in motion
Group Activity
INVESTIGATING MOMENTUM
GROUP PRESENTATION
INVESTIGATING MOMENTUM
GUIDE QUESTIONS:
Q1. How will you compare their stopping
distances?
Q2. Did the two toy cars hit the block of wood
immediately stop? As their point of release
increases, describe the stopping distances of the
two toy cars.
Q3. What do you think happens to the two toy
cars' velocity as the point of release increases?
GUIDE QUESTIONS:
Q4. Which of the two cars had a greater
momentum for the same release point, if
momentum is a measure of how difficult it is to
stop a moving object?
Q5. How will it be possible for the two bodies of
different masses to have equal momentum?
GUIDE QUESTIONS:
Q1. How will you compare their stopping
distances?
The stopping distance for the heavy toy car is
longer than the stopping distance for the light
toy car
GUIDE QUESTIONS:
Q2. Did the two toy cars hit the block of wood
immediately stop? As their point of release
increases, describe the stopping distances of the
two toy cars.
No. The stopping distance increases as the point of
release increases.
GUIDE QUESTIONS:
Q3. What do you think happens to the two toy
cars' velocity as the point of release increases?
The velocity increases as the point of release
increases
GUIDE QUESTIONS:
Q4. Which of the two cars had a greater
momentum for the same release point, if
momentum is a measure of how difficult it is to
stop a moving object?
The heavy toy car had greater momentum.
GUIDE QUESTIONS:
Q5. How will it be possible for the two bodies of
different masses to have equal momentum?
The less massive body should have a greater
velocity than the more massive body.
FOR BODIES MOVING AT
THE SAME VELOCITY, THE
MORE MASSIVE BODY HAS
GREATER
INERTIA
IN
MOTION THEREFORE HAS
GREATER MOMENTUM
Figure 1. (Two vehicles of different masses are
moving at the same velocity)
Figure 2. (Two identical cars of different
velocities)
FOR MOVING BODIES WITH THE SAME MASS,
THE FASTER BODY HAS GREATER INERTIA IN
MOTIONTHEREFORE
HAS
GREATER
MOMENTUM
MOMENTUM
The momentum (p) of a body is the product of its
mass (m) and its velocity (v), as in the equation:
p = mv.
IMPULSE
IN PHYSICS, AN EXTERNAL FORCE ACTING ON
AN OBJECT OVER A SPECIFIC TIME LEADS TO A
CHANGE IN MOMENTUM OF THE OBJECT
A SPECIAL NAME IS GIVEN TO THE PRODUCT OF
THE FORCE APPLIED AND THE TIME INTERVAL
DURING WHICH IT ACTS: IMPULSE. I = Ft
IMPULSE
IN PHYSICS, AN EXTERNAL FORCE ACTING ON
AN OBJECT OVER A SPECIFIC TIME LEADS TO A
CHANGE IN MOMENTUM OF THE OBJECT
Impulse is the change in momentum
Ft = ∆ p
Ft = m (vf-vi)
Activity 3 – Keep me Safe
Directions: Identify the material that reduces the force of impact
described in each situation.
Activity 3 – Keep me Safe
Directions: Identify the material that reduces the force of impact
described in each situation.
_______ 1. There is a mechanical failure in the plane. I need to jump off
the plane before it crashes. What do I need to do to land safely?
_______ 2. I got in a head-on collision with an electrical post but I was
not thrown forward. What
keeps me from my seat?
_______ 3. My car is out of control. I could collide with a mango tree or a
banana groove. Which
will I choose?
_______ 4. My car got into a head-on collision and both our cars
crumpled instead of rebounding.
Both of us are not seriously harmed because crumpling increases the
time of
changing our momentum thus reducing the impact force. What did car
manufacturers design into our cars to reduce injury?
_______ 5. My car accidentally hit the motorcycle that was trying to
overtake me. The driver and
his motorcycle were knocked over. He did not suffer serious head injury.
What did he
use to avoid serious head injury?
_______ 6. Fragile goods such as glass, ceramics, and electronic
products are transported safely
without breaking. What is placed inside the shipping package to prevent
breakage?
4
1
6
3
5
2
MODIFIED TRUE or FALSE
Directions: Write TRUE if the statement is correct and FALSE if the statement is incorrect
and underline the word that makes the sentence wrong.
1. Mass and velocity are the factors that affect momentum
2. The product of the force applied and the time interval during which it acts is known as
momentum.
3. Momentum is directly proportional to the velocity and mass of the object.
4. In stationary objects where the velocity is zero, the momentum is also zero.
5. Impulse is the product of time and force, and also it is equal to the change in
momentum?
Use the impulse-momentum equation to answer questions 1-3:
1. Why are airbags and crumple zones used in automobiles?
2. Why does it hurt more when you fall on a concrete floor than on a wooden floor?
3. Why are car dashboards, steering wheels, and boxing gloves padded?