Physics Momentum and Collisions Quiz

A block of mass 4kg travelling at 15m/s collides with another block of mass 3kg travelling at 8m/s in the opposite direction. Find the velocities of the 3kg block after the collision if the 4kg block comes to rest after the collision.

• 15 m/s in the original direction of the 4kg block

• 23 m/s in the original direction of the 3kg block

• 5 m/s in the original direction of the 3kg block

• None of the above

Two wagons are moving in the same direction along a horizontal track. The front wagon, of mass 500 kg, is moving at 3 m/s. The rear wagon, of mass 800 kg, is moving at 5 m/s. As a result of the collision the speed of the rear wagon is reduced to 4 m/s. Find the speed of the front wagon after the collision.

• 2 m/s

• 3 m/s

• 4.6 m/s

• 4.2 m/s

Two children sit on swings facing each other. Ann has a mass 40 kg, Ben has mass 30 kg. Their swings are pulled away from each other and released, so that the children meet when their swings are vertical. Ann is then moving at 2 m/s, and Ben is moving at 3 m/s. When they meet, they push each other away with their feet. Ann is then moving at 1.6 m/s. How fast is Ben moving?

• 2.4 m/s

• 1.8 m/s

• 3.2 m/s

• 3.6 m/s

A car of has mass 1200 kg and is travelling at 20 m/s. A lorry has mass 3500 kg and is travelling in the opposite direction to the car at 12 m/s. Calculate the momentum of the car and the momentum of the lorry.

• 24000 kg m/s for the car and 42000 kg m/s for the lorry

• 24000 kg m/s for the car and -42000 kg m/s for the lorry

• 12000 kg m/s for the car and 42000 kg m/s for the lorry

• 12000 kg m/s for the car and -42000 kg m/s for the lorry

A toy train, of mass 200 g, is moving along a straight line track at 1.8 m/s, when it collides with a stationary carriage of mass 300 g. During the collision the train and carriage are coupled together. Find the speed of the train and carriage after the collision.

• 1.2 m/s

• 1.0 m/s

• 0.72 m/s

• 1.5 m/s

Two particle travel towards each other along a straight line. One has mass 3 kg and speed 4 m/s. The other has mass 5 kg and speed 4 m/s. When they collide the 3 kg mass is brought to rest. What happens to the 5 kg mass?

• It continues to move in the same direction at the same speed.

• It comes to rest.

• It moves in the opposite direction at a different speed.

• It continues to move in the same direction but at a different speed.

A particle A of mass 250g collides with a particle B of mass 150g. Initially A has a velocity 7 m/s and B is at rest. After the collision, the velocity of B is 5 m/s. Calculate the velocity of A after the impact.

• 3 m/s

• 4 m/s

• 2 m/s

• 1 m/s

A child of mass 40 kg jumps onto a stationary skateboard of mass 4 kg. If the child was moving horizontally at 3.3 m/s just before he lands on the skateboard, find the speed at which they move.

• 3.0 m/s

• 3.3 m/s

• 3.6 m/s

• 4.0 m/s