Question

Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at $100^{\circ} C$ , while the other one is at $0^{\circ} C$. If the two bodies are brought into contact, then, assuming no heat loss, the final common temperature is -

• A. $50^{\circ} C$
• B. more than $50^{\circ} C$
• C. less than $50^{\circ} C$ but greater than $0^{\circ} C$
• D. $0^{\circ} C$

Answer 1

Answer: (B)

more than $50^{\circ} C$

Answer 2

Due to temperature heat capacity increase so heat capacity of second will greater than first. Let heat capacity are $c_1$ & $c_2$ and common temperature T so
$mc_1 (T - 0) = mc_2 (100 -T)$
$\frac{T}{100 - T} = \frac{c_2}{c_1} > 1$ \hspace20mm \\{c_2 > c_1\\}
$T > 50$