1. What initial velocity is required, at the ground, so that an object will reach a maximum height of 9 m? (use conservation of energy equations) 2. A 1000 kg car changes its velocity from 10 m/s to 24 m/s in 8 s. Calculate the work and power of the engine. 3. A crate of mass 50 kg is being pulled with a force of 30 N at an angle. The work done to pull the crate 15 m was 300 J. At what angle was the crate being pulled? 4. A person carries a 50 kg object up a flight of stairs. There are ten stairs; each step is 30 cm high and 30 cm deep. How much work is done to carry the object to the top of the stairs? 5. A roller-coaster cart (250 kg) is traveling at 5 m/s on the track that is 20 m above the ground. Calculate how fast is it traveling if it drops down a hill 6 m (it is therefore only 14 m from the ground at this point)?