Question

When you lift an object, two forces act on it. Identify these forces. Which one of the two does,

(a) positive work

(b) negative work

Answer 1

Here, the displacement is along the vertical direction. The displacement of the object is opposite to the direction of gravity. So, work done by gravity is negative. Here also, student is doing a positive work as the the force applied by him is in the same direction as that of displacement.and the work done by student is stored as the potential energy of the object..