Q. A body floats in water with 40% of its volume outside water. When the same body floats in an oil, 60% of its volume remains outside oil. The relative density of oil is
A) 0.9
B) 1.0
C) 1.2
D) 1.5
Explanation
(d) $V\sigma f = 0.6V\sigma_{1}g$
$V\sigma g = 0.4V\sigma_{2}g$
$\therefore\ \ \ \ \ \ \ 1 = \frac{6}{4}\ \frac{\sigma_{1}}{\sigma_{2}}$
$\therefore\ \ \ \ \ \ \ \frac{\sigma_{2}}{\sigma_{1}} = \frac{3}{2} = 1.5$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.