Question

A man who raises a mass m and height h and then shifts it horizontally over a distance. Find the wd against the gravity

Answer 1

The work done against the gravity is zero.

This is because that the force acts vertically downwards. While the displacement is along horizontal.

They are perpendicular to each other.

$wd = f.s$

In dot product,

$wd = fs \cos(90)$

So work done is 0.