A vessel contains oil of density 0.8 g /`cm^(3)` over mercury of density 13.6 g/`cm^(3)`. A homogeneous sphere floats with half of its volume in oil and other half immersed in mercury. The density of the material of the sphere in g /`cm^(3)` is :

Options

A. 3.3
B. 6.6
C. 7.2
D. 2.8

Answer

C

Explanation

Here Let V be the volume of the sphere.
Then Vpg=`(V/2)13.6g+V/2xx0.8xxg`
or `p=(13.6+0.8)/2=7.2g//cm^(3)`
Correct choice is (c).