Question

The densit of a block of wood which flots on water with 0.1 of its volume above water is:
A. `10^(3)kg//m^(3)`
B. `1.1xx10^(3)kg//m^(3)`
C. `0.9xx10^(3)kg//m^(3)`
D. `0.8xx10^(3)kg//m^(3)`

Answer 1

Correct Answer - C
Fraction of the volume of the body above the liquid i.e.,
`f_(out)=1-f_("in")=1-(rho)/(sigma)` (as `f_("in")=(rho)/(sigma)`)
Here, as `f_(out)=0.1,0.1=1-(rho)/(sigma)or(rho)/(sigma)=0.9`
or `rho=0.9sigma=0.9xx10^(3)kg//m^(3)`