Question

A cork of density $0.5g{cm}^{-3}$ floats on a calm swimming pool. The fraction of the cork's volume which is under water is

• A. $0$%
• B. $25$%
• C. $10$%
• D. $50$%

Answer 1

Answer: (D)

$50$%

Let the fraction $f$ of volume $V$ be submerged under water. We have
weight of cork=weight of water displaced
$\Rightarrow V\times 0.5\times g=f\times V\times 1\times g$
$\Rightarrow f=0.5$ or $50$%