Question

A ball is dropped from a window and takes 2 seconds to reach the ground. it starts from rest and reaches a final speed of 20 m/s. what is the ball's acceleration?

Answer 1

Acceleration of the ball is 10 $m/s^{2}$.

The relation between initial velocity , final velocity , acceleration and time can be written as,

v = u + at

Here, v is the final velocity, u is the initial velocity, a is the acceleration and t is the time

Time taken by ball to reach the ground = t = 2 seconds.

As it starts from rest , initial velocity of ball = u = 0 m/s.

Final velocity of ball = v = 20m/s.

v = u + at                                                               equation 1

Put value of v = 20m/s , u = 0m/s and t = 2 seconds in equation 1.

(20m/s) = (0 m/s) + a (2 second)

a = ( 20m/s )/( 2second )

a = 10 $m/s^{2}$

Acceleration of the ball is 10 $m/s^{2}$.

To know more about Acceleration refer to the link:

https://brainly.com/question/460763

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