A ball is thrown upward with a speed and direction such that it reaches a maximum height of 18.0 m above the point it was released. At its maximum height it has a speed of 20.0 m/s. With what speed was the ball released?
A)27.4 m/s
B)24.3 m/s
C)35.1 m/s
D)31.3 m/s
E)39.0 m/s

Question

Quizplus · Accepted Answer

At maximum height, the ball's velocity is zero. So, using the equation of motion, v^2 = u^2 + 2as, we have 0 = u^2 - 2(9.8)(18). Solving for u, we get u = 27.4 m/s.

A Ball Is Thrown Upward with a Speed and Direction