A mass of 10 kg is dropped from a height of 50 cm

cbse
workandenergy

#1

A mass of 10 kg is dropped from a height of 50 cm. Find its
(i) potential energy just before dropping.
(ii) kinetic energy just on touching the ground,
(iii) velocity with which it hits the ground.


#2

Given, mass of the object, m = 10 kg , Height, h = 50 cm= 0.5 m
(i) As potential energy is given by PE = mgh
= 10 x 10 X 0.5 = 50 J
(ii) From law of conservation of energy,
total energy of the ball just before dropping = total energy of the ball just on touching the ground => KE + PE of ball just before dropping
= KE of ball just on touching the ground = KE= 50 J
(iii)As , we know KE = 50J
so, 1/2 m ${{v}^{2}}$ = 50
${{v}^{2}}$ = 50 x 2/10 = 10