Aphysics student drops a rock from a 55m cliff. how long does it take to hit the ground?

A physics student drops a rock from a 55 m cliff, it takes 3.35 seconds to hit the ground.

Solution:

Using the second equation of motion,

Where, U= initial velocity of ball

S = distance at which rock is dropped from cliff = 55 m

t = time period

a = acceleration due to gravity = 9.8 m/s

Since the ball is dropped from cliff, initial velocity is zero.

u = 0