Question

A soccer ball is dropped from the height of 2m and falls to the floor. What is the relationship of the potential and kinetic energies of the ball as the ball falls to the floor?

Answer 1

We know , gravitational force is a conservative force .

Therefore , total energy of the system remains constant .

$P.E_i+K.E_i=P.E_f+K.E_f$

Let , mass of object is m.

So ,

$mg(2)+0=0+\dfrac{mv_f^2}{2}\\\\v_f=\sqrt{4g}\\\\v_f=\sqrt{4\times 9.8}\ m/s\\\\v_f=6.26\ m/s$

Therefore , the velocity at floor is 6.26 m/s .

Hence , this is the required solution .