Question

A rock falls for 4 seconds. How far did it fall

Answer 1

Answer:

d = 80 m

Explanation:

It is given that,

A rock falls for 4 seconds.

We need to find how far did it fall.

let it cover d distance.

Using equation of motion to find it :

$d=ut+\dfrac{1}{2}at^2$

Here, u = 0 (at rest initially)

a = g

$d=\dfrac{1}{2}gt^2\\\\d=\dfrac{1}{2}\times 10\times 4^2\\\\d=80\ m$

It will fall at a distance of 80 m.