Question

A piece of wood if left under water, comes to the surface. Explain the reason.

March 17, 2024

Answer

When a piece of wood is left under water, two forces act on it, (i) it’s weight (i.e., the force due to gravity) W which pulls it downwards, and (ii) the upthrust F_B due to water which pushes the wood upwards. The piece of wood comes to the surface because upthrust on the wood is more than the weight of the wood (i.e.,F_B > W ).

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