Question

A rock falls of a cliff and falls for 3 seconds. How high was the cliff?

Answer 1

The height of the cliff was 44.1m

Step-by-step explanation:

Answer 2

In this question we have given

time,t = 3 s

here rock is falling from a cliff, Therefore, in this case gravitational acceleration will act on rock which is g=
`9.8(m)/(s^(2) )`

Let s be the height of cliff

here, initial velocity of rock,u=0

we know from second equation of motion

`s=ut+.5at^(2)`............(1)

here a=g=
`9.8(m)/(s^(2) )`

put values of u,t and a in equation (1)

`s=0+.5*9.8(m)/(s^(2) ) *3^(2)s^(2)`

`s=44.1m`

therefore, height of the cliff is 44.1m