Question

If copper floats on mercury, and gold sinks in mercury, then which one of the following statements is TRUE?

• A. Copper is less dense than gold.
• B. Mercury is denser than gold.
• C. Copper is more dense than mercury.
• D. Mercury is the least dense of the three metals.

Answer 1

The correct option is A Copper is less dense than gold.

Relatively denser object sink in relatively less dense material.

Since copper floats in mercury,

${\rho }_{copper}<{\rho }_{mercury}$

Since gold sinks in mercury,

${\rho }_{gold}>{\rho }_{mercury}$

$⟹{\rho }_{gold}>{\rho }_{mercury}>{\rho }_{copper}$