Q7. Iqbal has to push a lighter box and Seema has to push a similar heavier box on the same floor. Who will have to apply a larger force and why?
Seema would have to apply a larger force as she would have to overcome a greater frictional force. The frictional force between two surfaces exists due to the interlocking of the irregularities on the surface. The magnitude of this frictional force depends on how tight this interlocking is which in this case depends on the weight of the boxes which is more in case of Seema.