A cubic body floats on mercury with 0.25 fraction of its volume below the surface. What fraction of the volume of the body will be immeresed in the mercury if a layer of water poured on top of the mercury covers the body conpletely.

Answer

A

Explanation

`w=(0.25)Vrho_(Hg)g`…(i)
Let x fraction of volume is immersd in mercury in the second case, Then

`w=xVrho_(Hg)g+(1-x)Vrho_(w)g` …(ii)
Equanting Eqs, (i) and (ii), we have
`(rho_(Hg))/(4)=xrho_(Hg)+(1-x)rhp_(w)`
`:. 12.6x=2.4`
or, `x=0.19`