When two spring balances joined at their free ends, are pulled apart, both show the same reading. Explain.

To move a boat ahead in water, the boatman has to push the water backwards by his oar. Explain.

A light ball falling on ground, after striking the ground rises upwards. Explain the reason.

A boy pushes a wall with a force of 10 N towards east. What force is exerted by the wall on the boy?