Chapter 14.3, Problem 69E

Initial speed of a golf shot A golfer stands 420 ft horizontally from the hole and 50 ft above the hole (see figure for Exercise 67). If the ball leaves the ground at an initial angle of 30° with the horizontal, with what initial speed should it be hit to land in the hole?

Another golf shot A golfer stands 420 ft (140 yd) horizontally from the hole and 50 ft above the hole (see figure). Assuming the ball is hit with an initial speed of 120 ft/s, at what angle(s) should it be hit to land in the hole? Assume the path of the ball lies in a plane.