1. Archimedes' Principle: This principle states that the buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid displaced by the object.
  2. Effective Weight in a Liquid: When an object is placed in a liquid, it displaces an amount of liquid equal to its own volume. The buoyant force acting on the object is then equal to the weight of this displaced liquid.
  3. Net Force: The net force acting on the object is the difference between its weight in air and the buoyant force in the liquid.Net Force=Weight in Air−Buoyant ForceNet Force=Weight in Air−Buoyant Force
  4. Apparent Weight: The apparent weight of the object in the liquid is the force it exerts on the scale (or any support) when submerged.Apparent Weight=Weight in Air−Buoyant ForceApparent Weight=Weight in Air−Buoyant Force
  5. Weight Reduction: If the buoyant force is greater than the weight of the object, the apparent weight will be less than the weight in air. In some cases, the apparent weight may be zero, and the object appears to float.

In summary, the weight of a body in a liquid is effectively reduced due to the buoyant force acting on it. This effect is more pronounced for objects that are less dense than the liquid they are submerged in. Objects with a density greater than the liquid will sink, and the apparent weight will still be less than the weight in air, but not reduced as much as for floating objects.

Further Reading