Question

A ball is thrown vertically upwards with an initial velocity of 20m/s comes to stop in 4s. Find retardation

Answer 1

Answer:

-5m/s

Explanation:

Initial velocity(Vo)=20m/s

Final velocity (Vt)=0m/s

Vt=Vo+at

0 =20+4a

-4a=20

a =20/-4=-20/4=-5m/s

Retardation = -5 m/s

Answer 2

Answer:

5 m/s²

Explanation:

Given, u = 20 m/s

v = 0

t = 4s

Acceleration a = v - u / t

= 0 - 20 m/s / 4s

= - 5 m/s²

Hence , retardation = 5 m/s²

Acceleration:

Acceleration is the rate of change of velocity with time.

Acceleration = Change in velocity / time interval