A body rolls down a slope from a height of 100m. its velocity at the foot of the slope is 20ms-1. What percentage of its initial potential energy is converted into kinetic energy? [g = 10ms-1]
-
A.
40% -
B.
35% -
C.
20% -
D.
15%
Correct Answer: Option C
Explanation
P.E = mgh = 1000m joules
K.E = (frac{1}{2})mv2 = 200m joules
%converted = (frac{200m}{1000m}) x 100
= 20%