A stone of mass 300g is released from rest from the top of a bulding of height 100m. Determine the kinetic energy gained by the stone when it is a quarter way down from the point of release.[g = 10 ms-2]
-
A.
750.0J -
B.
225.0J -
C.
75.0J -
D.
22.5J
Correct Answer: Option C
Explanation
K.E = P.E = mgh
= 0.3 x 10 x 100 – 0.3 x 10 x 75
= 75J