You are holding ball at the height of 1.5 meters m = 2 kg h =...

According to the law of conservation of energy total mechanical energy remains constant in the case of freely falling body.

The initial potential energy of a body at a height is E_P=mgh

= 2x9.8x1.5 =29.4J = E (release)

The final kinetic energy of the body at 0 is E_K =29.4J = E (impact)

Now the velocity with which it reached to the point 0 is v

Using the equation of motion

Here s= h = 1.5m

u= 0 initial velocity

v= final velocity which is to be determined

a= g =9.8m/s² , acceleration due to gravity

Now v² -0 = 2x9.8x1.5= 29.4

v² =29.4

This is velocity of impact v = 5.42m/s