2019 · Q59
Two identical solid pieces, one of gold and other of silver, when immersed completely in water exhibit equal weights. When weighed in air (given that density of gold is greater than that of silver)
General KnowledgePhysics
- Athe gold piece will weigh more
- Bthe silver piece will weigh more
- Cboth silver and gold pieces weigh equal
- Dweighing will depend on their masses
Explanation
The apparent weight in water equals the true weight minus the buoyant force. Since the two apparent weights are equal, W(gold) - rho(water)*V(gold)*g = W(silver) - rho(water)*V(silver)*g. Because gold is denser than silver, equal apparent weights force the silver piece to have the larger volume and the larger true weight in air - the greater buoyancy on the bigger silver piece exactly offsets its greater true weight. Hence the silver piece weighs more in air. Hence option B is correct.