Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Thermodynamics

Question:

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

Options:

50° C 

More than 50° C

Les than 50°C but greater than 0°C

0°C

Correct Answer:

More than 50° C

Explanation:

Heat lost by hot body = Heat gained by cold body

\({c_{1}} \Delta \theta_1 = {c_{2}} \Delta \theta_2 \)

$c_1$ is average heat capacity of body 1 and $c_2$ is average heat capacity of body 2.

As $c_1 > c_2$ ⇒ $\Delta\theta_1 $ < $\Delta\theta_2$

⇒ Increase in temperature of second body is more than drop of temperature in body 1. 

⇒ Final temperature > 50°C.