Q. A body floats in water with one-third of its volume above the surface of water. If it is placed in oil, it floats with half of its volume above the surface of the oil. The specific gravity of the oil is
A) $\frac{5}{3}$
B) $\frac{4}{3}$
C) $\frac{3}{2}$
D) $1$
Explanation
(b) Weight of body
$=$ weight of water displaced
= weight of oil displaced
$\Rightarrow \frac{2}{3}V\rho_{w}g = \frac{1}{2}V\rho_{0}g$
$\Rightarrow \rho_{0} = \frac{4}{3}\rho_{w}$
$\therefore$ Specific gravity of oil $= \frac{\rho_{0}}{\rho_{w}} = \frac{4}{3}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.