The ratio of the densities of the materials of two bodies is `2:3` and that of their specific heat capacities is `0.12:0.09`. Find the ratio of their thermal capacities per unit volume.

Explanation

Let the densities of two substances be `rho_(1) and rho_(2)`.and their specific heats be `s_(1) and s_(2)`, respectively.
According to the question, `rho_(1)=rho_(2)=2:3`
`s_(1):s_(2)=0.12:0.09`
Let their thermal capacities per unit volume be `H_(1) and H_(2)` respectively. As mass per unit volume is density `rho`, we have thermal capacity per unit volume `=rho.s.`
`therefore" "(H_(1))/(H_(2))=(rho_(1)s_(1))/(rho_(2)s_(2))=(2)/(3)xx(0.12)/(0.09)=(8)/(9).`