Question

The ratio of densities of two bodies is 5 : 6 and their specific heat in the ratio 3 : 5. The ratio of their thermal capacities per unit volume is:

• A. 25:18
• B. 1:2
• C. 2:1
• D. 1:1

Answer 1

The correct option is B 1:2

$\frac{d_A}{d_B}=\frac{5}{6};\frac{S_A}{S_B}=\frac{3}{5}$
$Thermalcapacity/unitvolumeoftwobodies=\frac{C_1}{C_2}$
$\therefore \frac{C_1}{C_2}=\frac{\frac{m_A}{V^{\prime }}\times S_A}{\frac{m_B}{V^{\prime }}\times S_B}=\frac{d_A}{d_B}\times \frac{S_A}{S_B}$

$=\frac{5}{6}\times \frac{3}{5}=\frac{1}{2}=1:2$