Question

A rocket is launched straight upward with a velocity of 90 m/s. It slows down, reverses direction, and returns to earth. what is the rockets velocity at its highest point above the ground.

a. 0.078 m/s
b. 0 m/s
c. -7.0 m/s
d. 13 m/s
e. -13 m/s

Answer 1

This is a kinematics problem. But, since the rocket's velocity is asked at the highest point, it will be 0m/s because it comes to a stop for a fraction of a second. The answer is b.

Answer 2

Answer: 0 m/s

The rocket is launched straight upward with a velocity of 90 m/s, At the highest point, the instantaneous velocity would be 0 m/s. The rocket slows down while moving up. The velocity would be 0 m/s at the highest point for an instant and then reverses direction to return on Earth. If it is not controlled, then it would free fall under gravity.