Question

A ball of mass of 0.5kg is dropped from a height of 2m.

Answer 1

Answer:

6.3m/s

Explanation:

Given parameters:

Mass of the ball  = 0.5kg

Height  = 2m

Unknown:

Velocity when the ball hits the ground  = ?

Solution:

Since the potential  energy is transformed into kinetic energy;

            P.E  = K.E

              mgh  = $\frac{1}{2}$ m v²

     cancelling m;

               gh  =  $\frac{1}{2}$ v²

                v² = 2gh

                v  = √2gh

Insert the parameters and solve;

               v  = √2gh  = √ 2 x 9.8 x 2  = 6.3m/s