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Physics – Momentum – Unit Review
Kowinsky
NAME: ___________________
Pd: _____
Concepts:
1) Define impulse
2) During what type of collision is Energy not conserved?
3) What type of collision applies more force, an inelastic or an elastic (bouncing)? Why?
4) Give 2 examples of a Perfectly elastic collision, and two examples of inelastic collisions.
5) If the time of impact during a collision increases, what happens to the force?
6) What is the momentum of a stationary object?
7) A truck loaded with sand is on a straight path. A) What happens to the momentum of the
truck if the truck’s velocity is increasing? B) What happens to the momentum of the
truck if sand leaks at a constant rate through a hole in the truck bed while the truck
maintains a constant velocity?
8) For safety reasons, it is recommended that a heavy load is not regularly carried in the
back of a pickup truck. Explain why in terms of momentum.
9) How do car bumpers that collapse on impact help protect the driver?
10) Who is Pelton, what did he do?
Impulse:
11) A football punter accelerates a .55 kg football from rest to a speed of 8 m/s in .25 s. What
force does the punter exert on the ball? (18 N)
12)What is the momentum of a proton with mass 1.67 x10-27 kg moving with a velocity of 5x106
m/s upward? (8.35x10-21 kg m/s).
Physics – Momentum – Unit Review
NAME: ___________________
Kowinsky
Pd: _____
13) If a .147 kg baseball has a momentum of 6.17 kg m/s as it is thrown from home to second
base, what is its velocity? (42 m/s toward second base)
14) A .025 kg golf ball moving at 18 m/s crashes through a windows of a house in 5x1—4 s.
After the crash, the ball continues the same directions with a speed of 10 m/s. What is the force
exerted on the ball by the window? (400 N).
Collisions:
15) An ice skater (ignore friction) is moving to the right with a velocity of 2.5 m/s. the ice skater
throws a .15 kg snowball to the right with a velocity of 32 m/s. What is the velocity of the ice
skater after throwing the snowball? (2.43 m/s to the right).
16) A 95 kg fullback moving south with a speed of 5 m/s has a perfectly inelastic collision with a
90 kg opponent running north a 3 m/s. How much KE was lost during the collision? (1400 J)
17) A .015 kg marble moving to the right at .225 m/s makes an elastic head on collision with a
.03 kg shooter marble moving to the left at .18 m/s. After the collision, the smaller marble
moves to the left at .315 m/s. What is the velocity of the .03 kg marble after the collision. Since
this is an elastic collision verify that KE is conserved. (.09 m/s to the right, KEi = .00087 J =
KEf)
18.) Object A has a mass of 5 kg, and is moving at a velocity of 3 m/s at 30o to the horizontal.
Object B has a mass of 3 kg, and is moving at a velocity of 5 m/s at 200o to the horizontal.
The two objects collide. Object B bounces at a velocity of 2 m/s at 70o to the horizontal.
Determine the velocity of object A after the collision.