Question

A stone of mass 'M' is taken to a height 'h' against gravitational pull; calculate the work done.

Answer 1

angle=90•

cos 90= 0

WD= F *cos 90*s

= F*0*s

=0

so, the WD is 0N

Answer 2

downward Force acting on particle M i.e.Mg

displacement of particle = h

work done =fdscos(angle b/w force and displacement)

Mgh cos(180)

-Mgh