Question

A 15 cm length of steel rod with relative density of 7.4 is submerged in a two layer fluid. The bottom layer is mercury and the top layer is water. The height of top surface of the rod above the liquid interface in 'cm' is

• A. 8.24
• B. 7.82
• C. 7.64
• D. 7.38

Answer 1

The correct option is D 7.38


$15\times A\times 7.4=x\times 1\times A+(15-x)A\times 13.6$
or
$x=\frac{15(13.6-7.4)}{12.6}=7.38cm$