Question

A piece of solid weighs 120 g in air, 80 g in water and 60 kg in a liquid. The relative density of the solid and that of the liquid are respectively.

• A.
• B.
• C.
• D.

Answer 1

Answer: (D)

Answer 2

Relative density of solid

$= \frac { 120 } { 120 - 80 } = \frac { 120 } { 40 } = 3$

Relative density of liquid

$= \frac { \text { weight in air } - \text { weight in liquid } } { \text { weight in air } - \text { weight in water } }$

$= \frac { 120 - 60 } { 120 - 80 } = \frac { 60 } { 40 } = \frac { 3 } { 2 }$

$= \frac { 120 } { 120 - 80 } = \frac { 120 } { 40 } = 3$