Question

A stone is thrown into a deep lake. As it sinks deeper and deeper into the water, the upthrust acting on it?
1. Decreases
2. First decreases then increases
3. Increases
4. Remains constant

Answer 1

Correct Answer - Option 4 : Remains constant

The correct answer is Remains constant.

• Once the stone is fully submerged, the buoyant force will remain unchanged because the volume of water that it displaces will remain unchanged. 

•  The buoyant force is a force acting on an object opposite to gravity by fluid which is being submerged partially or completely in the fluid.
  • It opposes the weight of the object.
  • The buoyant force is given by volume displaced by an object into the density of fluid into gravitational acceleration.
• The tendency of a body to float or to rise when submerged in a fluid testing an object's buoyancy.
• The buoyancy force is caused by the pressure exerted by the fluid in which an object is immersed.
  • The buoyancy force always points upwards because the pressure of a fluid increases with depth.