Assignment:
Question 1. An iron ball having a mass of 5 kg is lifted from the floor to a height of 2.5 meters above the floor.
a) How much work was done to lift the ball?
b) How much potential energy did the ball gain?
c) If the motor lifting the ball raises it 2.5 meters in ten seconds, what is its power?
Question 2. If a 600 kg car is moving with a speed of 25 m/s, that what is its kinetic energy? State your answer in Joules. What is its momentum? What are the correct units of measurement for momentum?
Question 3. A 200 g ball is thrown upwards with an initial kinetic energy of 10 Joules. What maximum height will the ball reach? (neglect air resistance).
Question 4. If a 200 g ball is dropped from 100 meters what is its velocity just before it hits the ground? What is its velocity after it has fallen halfway to the ground (50 m)? (neglect air resistance)
Question 5. Two bumper cars collide head-on. Before the collision, car 1 is coming from the right at 3 m/s and has a total mass of 200 kg. Car 2 is coming from the left at 5 m/s and has a total mass of 250 kg (the driver of car 2 is a lot fatter than the driver of car 1) At the time of the collision, the bumpers lock and the cars remain stuck together after the (inelastic) collision. Calculate the velocity (direction and speed) of the linked cars following the collision.