Exam 6: Linear Momentum and Collisions

Car A (mass = 1000 kg) moves to the right along a level, straight road at a speed of 6.0 m/s. It collides directly with car B (mass = 200 kg) in a completely inelastic collision. What is the momentum after the collision if car B was initially at rest?

As shown in Figure 6-2, a car (mass = 1500 kg) and a small truck (mass = 2000 kg) collide at right angles at an icy intersection. The car was traveling East at 20 m/s and the truck was traveling North at 20 m/s when the collision took place. What is the speed of the combined wreck, assuming a completely inelastic collision?

Why does ion propulsion, which expels material much faster than ordinary chemical rockets, hold such promise for future space travel?

The center of mass of an object must always be located where the physical material of the object is located.

Tightrope walkers walk with a long flexible rod in order to

A 0.32 kg ball is moving horizontally 30. m/s just before bouncing off a wall, thereafter moving 25. m/s in the opposite direction. (a) What is the magnitude of its change in momentum? (b) What percentage of the kinetic energy was lost in the collision?

What is the difference between "center of gravity" (cg) (cm)? When are they the same?

A toy rocket, of mass 60 g, achieves a velocity of 80 m/s after 3.0 s when fired straight up. What average thrust force does the rocket engine exert?

An arrow of mass 20. g is shot horizontally into a bale of hay, striking the hay with a constant velocity of 60. m/s. It penetrates a depth of 20. cm before stopping. What is the average stopping force acting on the arrow?

A car hits another and the two bumpers lock together during the collision. Is this an elastic or inelastic collision?

A 2.0 kg softball is pitched to you at 20. m/s. You hit the ball back along the same path, and at the same speed. If the bat was in contact with the ball for 0.10 s, the average force the bat exerted was

A proton, of mass m and speed v, strikes an alpha-particle (which consists of 2 protons and 2 neutrons) at rest. If the collision is completely elastic, what speed will the $\alpha$ -particle have after the collision? (Assume the neutron's mass equals the proton's mass.)

Car A (mass = 1000 kg) moves to the right along a level, straight road at a speed of 6.0 m/s. It collides directly with car B (mass = 200 kg) in a completely inelastic collision. What is the speed of the car immediately after the collision?

Two equal mass balls (one blue and the other gold) are dropped from the same height, and rebound off the floor. The blue ball rebounds to a higher position. Which ball is subjected to the greater magnitude impulse during its collision with the floor?

A car of mass M, traveling with a velocity V, strikes a parked station wagon, whose mass is 2M. The bumpers lock together in this head-on inelastic collision. What fraction of the initial kinetic energy is lost in this collision?

A sailboat of mass m is moving with a momentum p. Which of the following represents its kinetic energy?

When a car, moving at velocity v, collides head on with a light volley ball, initially at rest, the ball bounces off with velocity

A 1200. kg ferryboat is moving south at 20. m/s. Its momentum is

A ball, of mass 100. g, is dropped from a height of 12. m. Its momentum when it strikes the ground is

When a cannon fires a cannonball, the cannon will recoil backward because the