Deck 4: Momentum

Question 1

In a collision between two objects having unequal masses,how does magnitude of the impulse imparted to the lighter object by the heavier one compare with the magnitude of the impulse imparted to the heavier object by the lighter one?

A) The lighter object receives a larger impulse.
B) The heavier object receives a larger impulse.
C) Both objects receive the same impulse.
D) The answer depends on the ratio of the masses.
E) The answer depends on the ratio of the speeds.

Answer 1

Both objects receive the same impulse.

Question 2

A 480-kg car moving at 14.4 m/s hits from behind a 570-kg car moving at 13.3 m/s in the same direction.If the new speed of the heavier car is 14.0 m/s,what is the speed of the lighter car after the collision,assuming that any unbalanced forces on the system are negligibly small?

A) 13.6 m/s
B) 10.5 m/s
C) 19.9 m/s
D) 5.24 m/s

Answer 2

13.6 m/s

Question 3

As a tile falls from the roof of a building to the ground its momentum is conserved.

Answer 3

False

Question 4

Two ice skaters push off against one another starting from a stationary position.The 45.0-kg skater acquires a speed of 0.375 m/s.What speed does the 60.0-kg skater acquire? Assume that any other unbalanced forces during the collision are negligible.

A) 0.500 m/s
B) 0.281 m/s
C) 0.375 m/s
D) 0.750 m/s
E) 0.000 m/s

Question 5

You are standing on a skateboard,initially at rest.A friend throws a very heavy ball towards you.You can either catch the object or deflect the object back towards your friend (such that it moves away from you with the same speed as it was originally thrown).What should you do in order to MINIMIZE your speed on the skateboard?

A) Catch the ball.
B) Deflect the ball.
C) Your final speed on the skateboard will be the same regardless whether you catch the ball or deflect the ball.

Question 6

A 2.50-kg stone is dropped from rest at a height of 3.75 m.What impulse does gravity impart to this stone from the instant it is dropped until it hits the ground,assuming negligible air resistance?

Question 7

Two objects of the same mass move along the same line in opposite directions.The first mass is moving with speed v. The objects collide,stick together,and move with speed 0.100v in the direction of the velocity of the first mass before the collision. What was the speed of the second mass before the collision?

A) 1.20v
B) 10.0v
C) 0.900v
D) 0.800v
E) 0.00v