• Subject:

...

• Topic:

...

Consider two hot bodies ${\mathrm{B}}_{1}$ and ${\mathrm{B}}_{2}$ which have temperatures 100$°\mathrm{C}$ and 80$°\mathrm{C}$ respectively at t=0. The temperature of the surroundings is 40$°\mathrm{C}$. The ratio of the respective rates of cooling ${\mathrm{R}}_{1}$ and ${\mathrm{R}}_{2}$ of these two bodies at t=0 will be
(a) ${\mathrm{R}}_{1}:{\mathrm{R}}_{2}=3:2$       (b) ${\mathrm{R}}_{1}:{\mathrm{R}}_{2}=5:4$
(c) ${\mathrm{R}}_{1}:{\mathrm{R}}_{2}=2:3$       (d) ${\mathrm{R}}_{1}:{\mathrm{R}}_{2}=4:5$