Question

A block of iron is kept at the bottom of a bucket full of water at $2^{o}C$. The water exerts bouyant force on the block. If the temperature of water is increased by $1^{o}C$ the temperature of iron block also increases by $1^{o}C$. The bouyant force on the block by water:

• A. will increase
• B. will decrease
• C. will not change
• D. may decrease or increase depending on the values of their coefficient of expansion

Answer 1

The correct option is A will increase

Increasing the temperature of water from $2^{0}C$ to $3^{0}C$
increases its density of water and increases the volume of iron.
Hence the buoyant force which is product of volume of iron and density of water increases.