When person float in a swimming pool, he/she experiences an upthrust. What causes this effect?
The upthrust experienced by a person floating in a swimming pool is due to the principle of buoyancy. Buoyancy is the upward force exerted by a fluid that opposes the weight of an immersed object.
When a person enters the water and floats, the water exerts an upward force on their body, pushing them to the surface of the pool. This upward force is equal to the weight of the water that the person's body displaces. As a result, the person feels lighter and is able to float on the surface of the water.
This effect is caused by the difference in pressure at different depths in the water. The pressure at deeper depths is greater than at the surface, causing the water to push up on objects immersed in it. This upward force is what allows objects (such as a person) to float in the water.