Question

Two spheres A and B have diameters in the ratio 1 : 2, densities in the ratio 2 : 1 and specific heats in the ratio 1 : 3; find the ratio of their thermal capacities –

• A. (a) 1 : 6
• A. (b) 1 : 12
• A. (c) 1 : 3
• A. (d) 1 : 4

Answer 1

(b)

$\frac{H_{1}}{H_{2}}$= $\frac{m_{1}c_{1}}{m_{2}c_{2}}$= $\frac{\frac{4}{3}\pi r_{1}^{3}.\rho_{1}.C_{1}}{\frac{4}{3}\pi r_{2}^{3}.\rho_{2}C_{2}}$= $\frac{r_{1}^{3}}{r_{2}^{2}}$× $\frac{\rho_{1}}{\rho_{2}}$ × $\frac{C_{1}}{C_{2}}$