Question

In which of the following cases is the work done positive, negative or zero?

(a) Work done by a porter on lifting a suitcase from the platform on his head.

(b) Work done by gravity on lifting a suitcase by porter from the platform on to his head​

Answer 1

Answer:

Explanation:

A) Positive = Force and displacement in same direction.

B) Positive = Force of gravity and displacement by falling  are in same direction