Question

4) The average velocity of freely falling body is 21 ms-1. Then it is released from a height equal to
a)5m
b) 90m
c) 30m
d) 60m​

Answer 1

ANSWER :

As the object is free falling, so, u=0,

given, v-u=21, therefore, v=21.

Hence, u=v+at (a is acceleration due to gravity)

0=21+9.8*t

=> t=-21/9.8= 2.15 approx.

Now, s=it+1/2at^2

=> s=0+1/2*(2.15)^2*9.8

l think you can make it after this...

Thanks