Exam 6: Momentum and Collisions

A 0.11-kg object moving initially with a velocity of +0.3 m/s makes an elastic head-on collision with a 0.17-kg object initially at rest.What percentage of the original kinetic energy is retained by the 0.11-kg object?

A model car is propelled by a cylinder of carbon dioxide gas.The cylinder emits gas at a rate of 4.5 g/s with an exit speed of 85.0 m/s.The car has a mass of 420 g,including the CO₂ cylinder.Starting from rest,what is the car's initial acceleration?

A billiard ball is moving in the x-direction at 30.0 cm/s and strikes another billiard ball moving in the y-direction at 40.0 cm/s.As a result of the collision,the first ball moves at 50.0 cm/s,and the second ball stops.What is the change in kinetic energy of the system as a result of the collision?

Object 1 has twice the mass of Object 2.Both objects have the same kinetic energy.Which of the following statements is true?

A baseball infielder,mass 73.0 kg,jumps up with velocity 2.5 m/s and catches a 0.185-kg baseball moving horizontally at 55.0 m/s.Of the following,which is closest to the final momentum of the system,infielder and baseball?

Popeye,of mass 79 kg,has just downed a can of spinach.He accelerates quickly and stops Bluto,of mass 680 kg (Bluto is very dense),who is charging in at 10 m/s.What was Popeye's speed?

When a collision is perfectly inelastic,then:

A 7.00-g bullet is fired into a 545-g block of wood suspended as a ballistic pendulum.The combined mass swings up to a height of 9 cm.What was the magnitude of the momentum of the combined mass immediately after the collision?

A 5.00-g bullet is fired into a 800-g block of wood suspended as a ballistic pendulum.The combined mass swings up to a height of 8.00 cm.What was the kinetic energy of the bullet immediately before the collision?

A 71-kg swimmer dives horizontally off a 450-kg raft.If the diver's speed immediately after leaving the raft is 6 m/s,what is the corresponding raft speed?

Object 1 has twice the mass of Object 2.Each of the objects has the same magnitude of momentum.Which of the following statements is true?

A 15.0-g bullet is fired into a 1,500-g block of wood which is suspended as a ballistic pendulum.The combined mass swings up to a height of 8.50 cm.What was the kinetic energy of the combined mass immediately after the collision?

A high-diver of mass 73 kg jumps off a board 10 m above the water.If,1.0 s after entering the water his downward motion is stopped,what average upward force did the water exert?

A billiard ball collides in an elastic head-on collision with a second stationary identical ball.After the collision which of the following conditions applies to the first ball?

A billiard ball (Ball #1)moving at 5.00 m/s strikes a stationary ball (Ball #2)of the same mass.After the collision,Ball #1 moves at a speed of 4.25 m/s.Find the speed of Ball #2 after the collision.

The units of impulse are equivalent to:

Two particles collide,one of them initially being at rest.Is it possible for both particles to be at rest after the collision?

A ball with original momentum +3.0 kg⋅m/s hits a wall and bounces straight back without losing any kinetic energy.The change in momentum of the ball is:

A helicopter stays aloft by pushing large quantities of air downward every second.What mass of air must be pushed downward at 35.0 m/s every second to keep a 1,050-kg helicopter aloft?

A railroad freight car,mass 16,000 kg,is allowed to coast along a level track at a speed of 2.0 m/s.It collides and couples with a 48,000-kg loaded second car,initially at rest and with brakes released.What percentage of the initial kinetic energy of the 16,000-kg car is preserved in the two-coupled cars after collision?