Question

A ballplayer catches the ball 4 seconds after throwing it straight up in the air. What speed did he throw it and how high did it go?

Answer 1

Speed of the ball when it was thrown = 16.67 m/s

Height reached by the ball = 14.16 s

Step-by-step explanation:

Given time in the ball comes to the same height from where the ball was thrown is 3.4 s.

Let us assume that the ball was thrown with a speed of u in the upward direction. Since only gravitational force acts on the particle in the downward direction, it has a constant acceleration in the downward direction.

We also know that a particle has the same magnitude of velocity when it is under a free fall at a fixed height but direction is opposite i.e., initially in the upward direction and finally in the downward direction.

`image`

Hence, the particle was thrown with a speed of 16.67 m/s.

Now, we also note that the particle has zero velocity at its maximum height.

So, from the initial position to the maximum height reached by the particle, we have

`image`

Hence, the maximum height reached by the ball is 14.16 m.