Question

A labourer is pushing a heavy stone with maximum force, but is unable to move it.

1. What is kind of equilibrium shown by the stone?
2. Name two sets of opposing forces acting on the stone.
3. Are the forces mentioned by you in equilibrium?

Answer 1

1. The stone is in static equilibrium because it remains at rest.
2. 1. The labourer’s pushing force and the frictional force opposing it.
   2. The stone’s weight acting downward and the normal reaction of the ground acting upward.
3. Yes. These forces balance one another, so the resultant force on the stone is zero.