Why does the stone lose weight when it is immersed ?

Explanation

1. Suspend a stone from a spring balance. Note the reading of the spring balance.
2. Take a beaker half filled with water.
3. Now immerse the stone in the water, note the reading of the spring balance.
4. We notice that the stone, when immersed appears to lose some weight.
5. The immersed stone appears to lose weight because the force of buoyancy.
6. Thus the apparent loss of weight must be equal to the force of buyancy acting on the immersed stone.