Question

A stone is suspended from a spring balance and immersed in water. Why does the reading of the spring balance reduce when the stone is immersed? Why is no further decrease in reading observed after the stone is fully immersed?
Plz answer guys, it's urgent​

Answer 1

Answer:

Due to the buoyant force

Explanation:

When the stone is immersed in water a buoyant force is exerted by the water onto the stone. Since the force of weight(mg) is downward and buoyant force is upward therefore these are added and the resultant force is mg-B; where B is the buoyant force. Now this resultant force is always downward or 0 and since mg-B < mg therefore the wt. measured is lesser than in air.

Once the stone is fully immersed the complete extent of the buoyant force is exerted so unless the volume of the stone is increased it is not possible for mg-B to decrease any further