A ball thrown upwards comes to a rest because of Earth's gravity, which tends to pull everything towards itself. Thus, the highest point of the ball is where it comes to a rest and its final velocity becomes 0. Using equation of motion:

v = u + at

where, v...

## Unlock

This Answer NowStart your **48-hour free trial** to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

Already a member? Log in here.

A ball thrown upwards comes to a rest because of Earth's gravity, which tends to pull everything towards itself. Thus, the highest point of the ball is where it comes to a rest and its final velocity becomes 0. Using equation of motion:

v = u + at

where, v is the final velocity = 0 m/s

u is the initial velocity

a is the acceleration and is equal to -g or -9.81 m/s^2 (acceleration due to gravity of Earth)

and t is time taken = 2 s

Substituting all the parametric values in the equation, we get:

0 = u + (-9.81 x 2)

or, **u = 19.62 m/s**.

Thus, the ball was thrown upwards with an initial speed of 19.62 m/s.

In general, anything that is thrown upwards is pulled down due to gravity and hence loses speed. Anything thrown downwards, gains speed due to acceleration due to gravity.

Hope this helps.