1. LINEAR IMPULSE
AND
MOMENTUM
ME113022 ZOHAIB AHMAD
ME11300 SAQIB AMIR
ME11300 M TAHA
ME11300 M RAMZAN
2. Impulse and Momentum
ASTRONAUT Edward H. White II is in the
zero gravity of space. By firing the gas-
powered gun, he gains momentum and
maneuverability. Credit: NASA ZOHAIB AHMAD MAJU
ISLAMABAD
4. Conservation of Linear
Momentum
The total linear momentum of a system of
objects is constant if the net force acting on a
system is zero.
Momentum
is conserved
in this rocket launch.
The velocity of the
rocket and its payload is
determined by the mass and
velocity of the expelled gases.
Photo: NASA
ZOHAIB AHMAD MAJU
ISLAMABAD
7. Collision Classifications
• Collisions are classified according to whether the
kinetic energy changes during the collision.
• The two classifications are elastic and inelastic.
• In an elastic collision the total kinetic energy of the
system is the same before and after the collision.
• In an a perfectly inelastic collision the total kinetic
energy is still conserved but the two objects stick
together and move with the same velocity.
ZOHAIB AHMAD MAJU
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9. Two billiard balls collide in a
perfectly elastic collision. Ball A
has a mass of 0.8 kg and an
initial velocity (u A) of 3 m/s, ball
B has a mass of 0.3 kg and an
initial velocity (u B) of −2 m/s,
determine the velocity of each
ball after the collision.
ZOHAIB AHMAD MAJU
ISLAMABAD
10. Two clay objects collide in an
inelastic collision, object A
has a mass of 0.8 kg and an
initial
velocity (u A) of 4 m/s, object
B has a mass of 0.4 kg and
an initial velocity (u B) of −2
m/s, determine the final
velocity of A and B.
ZOHAIB AHMAD MAJU
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11. IMPULSE
∆t
Impulse:
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12. Example 1: The face of a golf club exerts
an average force of 4000 N for 0.002 s.
What is the impulse imparted to the ball?
Impulse:
∆t
The unit for impulse is the newton -second (N-s)
Other units are dyne-second and pound-second (lb-s) ZOHAIB AHMAD MAJU
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13. Impulse Changes Velocity
and Momentum
Consider a mallet hitting a ball:
Impulse = Change in “m v”
Impulse = Change in “m v” ZOHAIB AHMAD MAJU
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14. Impulse-Momentum
The impulse – momentum relationship is derived from
Newton’s law of acceleration.
Impulse = change in
momentum ZOHAIB AHMAD MAJU
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15. Impulse and Momentum
Impulse = Change in momentum
F mv Newton’s Second Law of
Motion
∆t A force F acting on a ball for a time ∆t increases its momentum
mv. ZOHAIB AHMAD MAJU
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16. Momentum
Impulse
Impulse = Change in momentum
Impulse = Change in momentum
ZOHAIB AHMAD MAJU
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