Let us find the efficiency : Ans = 0.6
Explanation:
we know :
efficiency = output/input
We also know that :
output = m x g x h
where :
m = mass of body
g = acceleration due to gravity
h = height of body from floor
Thus, output = 0.6 x 10 x 1.2 = 7.2J
Similarly ,input = 0.6 x 10 x 2 = 12J
Thus efficiency = 7.2/12 = 0.6
