Question

A stone is dropped in a river surface of water,if it takes 4 seconds to reach surface of water, calculate the velocity with which the stone strikes on the water surface​

Answer 1

Answer:from,

v=at+u then ,time=4seconds

we take u=initial speed which is zero

(0)

 now, v=(10x4+0)m/s

then, velocity/speed is 40m/s

Explanation:from firt newton's laws of motion where from acceleration is rate of change of speed then we generate the eqn where now the stone was falling fat a certain height were we include acceleration due to gravity and multiply to time and sum to initial speed to get