Question

A body of mass $2kg$ is moving in a vertical circle of radius $2m$. The work done when it moves from the lowest point to the highest point is

• A. $80\mspace{6mu} J$
• B. $40\mspace{6mu} J$
• C. $20\mspace{6mu} J$
• D. 0

Answer 1

Answer: (A)

$80\mspace{6mu} J$

Answer 2

work done = change in potential energy $= 2mgr = 2 \times 2 \times 10 \times 2 = 80J$