Question

a stone is dropped from the edge of a roof.find the speed of the stone at 2 second after the stone was dropped

Answer 1

v = u+ at
v = 0+9.8(2)
=19.6m/sec

Answer 2

Here we have to use the formula:

V=U+AT

V= final velocity

U= initial velocity

T= time

A=acceleration

Here, We have to calculate the final velocity that is V

Now V=U+AT

U=0 ( In the initial the body is at rest)

A=9.8 m/s^2 ( earth's acceleration due to gravity)

T = 2 seconds (given)

By the condition,

V=0 + 9.8 × 2= 19.6 m/s

So, The speed of the body is 19.6 m/s