4. A rock is thrown upwards at 8.4 m/s from a bridge which is 28 m above the water. a) What is the maximum height above the water reached by the rock? C Ans: b) What is the rock's velocity just before it strikes the water below the bridge? Ans: c) How much time has passed when the rock hits the water? Ans: 5. At an amusement park, riders can sit on a chair and be lifted to a height of and then dropped. Mr. Cheung decides to try out this ride during a warm summer day. As Mr. Cheung is being lifted to the top of the ride at a constant speed of 4.5 m/s, he loses his sandal when he is 95.0 m above the ground. How long does it take the sandal to reach the ground? Ans: 6. You are standing below a cliff and toss a softball up to your friend who is standing on the edge of the cliff, 8.0 meters above you. The ball goes Up, up, up past your friend who then catches it on the way DOWN. The initial speed of the ball is 30 m/s. At what time will your friend catch the ball on the way down? Ans