An aluminium sphere is dipped into water. Which of the following is true ?

Options

A. Buoyancy will be less in water `0^(@)C` than that in water at `4^(@)C`
B. Buoyance will be more in water at `0^(@)C` than that in water at `4^(@)C`
C. Buoyancy in water at `0^(@)C` will be same as that in water at `4^(@)C`
D. Buoyance may be more or less in water at `4^(@)C` depending on the radius of the sphere

Answer

A

Explanation

Let volume of the sphere is V and p is its density, then we can write buyant force
F=V p G (g= acceleratuon due to gravity)
`rArr" "F prop p` (`therifore` V and g are almost constant)
`rArr" "(F_(4^(@)C))/(F_(o^(@)C))=(p_(4^(@)C))/(p_(o^(@)C))gt1`
Hence, buoyance will be less in water at `0^(@)C` than that in water at `4^(@)C.`