conservation of momentum

Consider a system to be one train car moving toward another train car at rest. When the train cars collide, the two cars stick together. What is the total momentum of the system after the collision?

2,400 kg • m/s

Two objects of mass m move in opposite directions toward each other. The green object moves at velocity v, and the blue object moves at velocity 2v. Which diagram correctly shows the direction and velocity for each of the objects after an elastic collision?

3rd pic (2v-[m] [m]-v)

Identify the conditions for an elastic collision in a closed system. Check all that apply

Energy is conserved. Velocities may change. Momentum is conserved. Kinetic energy is conserved One object may be stationary before the elastic collision.

Consider a system to be two train cars traveling toward each other. What is the total momentum of the system before the train cars collide? (1) What must the total momentum of the system be after the train cars collide? (2)

1) 1,600 kg • m/s 2) 1,600 kg • m/s

A cue ball has a mass of 0.5 kg. During a game of pool, the cue ball is struck and now has a velocity of 3 m/s. When it strikes a solid ball with a mass of 0.5 kg, the cue ball comes to a complete stop. What is the new velocity of the solid ball? Round your answer to the nearest whole number.

3 m/s

During a game of marbles, a player is trying to win a 2 g marble that is at rest. The player flicks a 1.25 g marble at a velocity of 8 m/s at the larger marble that is sitting still. After the collision, the smaller marble has a velocity of 1 m/s What is the velocity of the 2 g marble after the collision? Round your answer to the nearest whole number.

4 m/s

Train car A is at rest when it is hit by train car B. The two cars, which have the same mass, stick together and move off after the collision. How does the final velocity of train cars A and B after the collision compare to the initial velocity of train car B before the collision?

The final velocity is half of train car B's initial velocity.

Two balls, each with a mass of 0.5 kg, collide on a pool table. Is the law of conservation of momentum satisfied in this collision? Explain why or why not

Yes, the law of conservation of momentum is satisfied. The total momentum before the collision is 1.5 kg • m/s, and the total momentum after the collision is1.5 kg • m/s. The momentum stays the same after the collision.

Two billiard balls move toward each other on a table. The mass of the number three ball, m1, is 5 g with a velocity of 3 m/s. The mass of the eight ball, m2, is 6 g with a velocity of 1 m/s. After the balls collide, they bounce off each other. The number three ball moves off with a velocity of 5 m/s. What is the final velocity and direction of the eight ball?

+5.7 m/s