For the same pucks from Question 7, what is the speed of Puck 2 after the collision in ms^-1? (For this question, do not include the unit in your answer, just the number.)

Hint: you can either think about what the magnitude of the impulse of Puck 2 on Puck 1 must be and work it out from that, or use conservation of momentum.

Two hockey pucks (150g each) are travelling across the ice in a straight line. Puck 1 is travelling faster than Puck 2 and catches up with, and collides with, Puck 2. The initial velocity of Puck 1 was 3 ms^-1 and the initial velocity of Puck 2 was 2 ms^-1. After the collision, the speed of Puck 1 is 2 ms^-1.

What is the magnitude of the impulse of Puck 1 on Puck 2?

At a crash test facility scientists run a car of mass m into a wall at a velocity v. The car comes to rest following the collision. The experiment is repeated several times at the same velocity for several different cars (all of mass m).

Given that the mass of the cars and the velocity of the cars are all the same, what aspect of the collision can a car designer try to change to reduce the average force applied to the car (and hence to the occupants of the car)?

Which of the following options show a correct relation for impulse? (You may need to select more than one option.)

What is the average force applied by the ball on the wall? (The same ball from Questions 3 and 4.)

If the ball from Question 3 is in contact with the wall for 0.2 s what is the magnitude of the average force vector applied by the wall on the ball, in units of N? (For this question, do not include the unit in your answer, just the number.)

A tennis ball of mass 50g is hit against a wall. It hits the wall at 5 ms^-1 and rebounds in the direction it came from at 4 ms^-1.

 What is the magnitude of the total change in momentum of the tennis ball in kgms^-1 ? (For this question, do not include the unit in your answer, just the number.)

Hint: draw a sketch of the situation

A tennis ball of mass m is hit against a wall. It hits the wall at velocity u and rebounds in the direction it came from at velocity v.

Which formula gives the change in momentum of the tennis ball?