A solid of density 5000 kg m-3 weighs 0.5 kgf in air. It is completely immersed in water of density 1000 kg m-3. Calculate the apparent weight of the solid in water.

Density of the solid = 5000 kg m^-3

Weight of the solid = 0.5 kgf

Density of water = 1000 kg m^-3

Volume = 0.5/5000 = 0.1 × 10^-3 m³

Upthrust = 0.1 × 10^-3 × 1000 × g = 0.1 kgf

apparent weight = true weight – upthrust

Substituting the values we get,

apparent weight = 0.5 – 0.1 = 0.4 kgf