(b) (C) (d) Dene kinetic energy and gravitational potential energy. What is the SI unit for energy? ( 5 l A ping-pong ball and a golf ball have the same speed. Which one will have the larger kinetic energy? Explain your answer. i 3 l A tennis ball is thrown upwards with sufficient speed to reach a height of 12 m. (i) What is the kinetic energy of the tennis ball at a height of 12 m? (ii) Calculate the speed of the tennis ball when it reaches a height of 6 m. l 7 l A 100 N force that makes an angle of 30 with the horizontal is used to move a 10 kg crate across a smooth floor. The crate moves through a distance of 500 cm. Find the work done by the force. ( 5 l