A man starts walking from a point on the surface of earth (assumed smooth) and reaches diagonally opposite point. What is the nature of work done by him?

A man starts walking from a point on the surface of earth (assumed smo

1.	A man starts walking from a point on the surface of earth (assumed smooth) and reaches diagonally opposite point. What is the nature of work done by him?
Answer» zero positive negative nothing can be said Solution :`W=F.d=0` SINCE `d=(-x+x)=0` (DIAGONALLY OPPOSITE POINT)