A 4kg brick is dropped from the top of a building whose hight is 30m. what is the velocity with which it reaches the ground

=24.25 ^−1

Explanation:

Let   and   be initial and final velocity of the body respectively,  

be acceleration due to gravity ( 9.8^−2 ),  ℎ be the height of the body.

=0 ^ −1

ℎ=30

we know that, ^2−^ 2=2ℎ

^2=2∗9.8∗30

^2=588

=24.25 ^−1

f=ma newton's second law 7x8=56n