Exam 6: Momentum, Impulse, and Collisions

A tennis ball is held above and in contact with a basketball,and then both are simultaneously dropped.The tennis ball bounces off the basketball at a fairly high speed.This is because:

A 13.4-g bullet is fired into a 1.60-kg 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 20.0-g bullet moving at 1 000 m/s is fired through a one-kg block of wood emerging at a speed of 100 m/s.If the block had been originally at rest and is free to move,what is its resulting speed?

​A satellite engine has an exhaust speed of 2.80 × 10⁴ m/s and ejects ionized gas at a rate of 2.50 × 10^-6 kg/s.What is the instantaneous thrust of the engine?

Two masses collide and stick together.Before the collision one of the masses was at rest.Is there a situation in which the kinetic energy is conserved in such a collision?

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?

If the momentum of an object is tripled,its kinetic energy will change by what factor?

Kaitlin uses a bat to hit a thrown baseball.She knocks the ball back in the direction from which it came in a partially inelastic collision.The bat,which is heavier than the baseball,continues to move in the same direction after the hit as Kaitlin "follows through." Is the ball moving faster before or after it was hit?

A billiard ball is moving in the x-direction at 33.4 cm/s and strikes another billiard ball moving in the y-direction at 38.9 cm/s.As a result of the collision,the first ball moves at 50.6 cm/s,and the second ball stops.In what final direction does the first ball move?

A 5-kg object is moving to the right at 4 m/s and collides with a 4-kg object moving to the left at 5 m/s.The objects collide and stick together.After the collision,the combined object:

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

A 5-kg object is moving to the right at 4 m/s and collides with another object moving to the left at 5 m/s.The objects collide and stick together.After the collision,the combined object:

A moderate force will break an egg.However,an egg dropped on the road usually breaks,while one dropped on the grass usually doesn't break.This is because for the egg dropped on the grass:

Two billiard balls have velocities of 4.0 m/s and -1.0 m/s when they meet in an elastic head-on collision.What is the final velocity of the first ball after collision?

A 25.0-kg object sitting at rest is struck elastically in a head-on collision with a 20.5-kg object initially moving at +4.0 m/s.Find the final velocity of the 25.0-kg object after the collision.

In an inelastic collision between two objects with unequal masses:

A rock is moving with speed v.If the mass of the rock were tripled and the speed were reduced to v/3,which of the following statements would be true?

A 5.00-g bullet is fired into a 950-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 2 500-kg car moving north collides with a 2 000-kg car moving west.After the collision,the cars stick together and move at an angle of 45° north of west at a speed of 8.0 m/s.What was the initial speed of the 2 500-kg car?

Ann the Astronaut weighs 65.0 kg.She is space walking outside the space shuttle and pushes a 350.0-kg satellite away from the shuttle at 0.70 m/s.What speed does this give Ann as she moves toward the shuttle?