# Heat capacity of thermal energy reservoir (TER) - Thermodynamics

**Q. A thermal energy reservoir (TER) has***- Published on 19 Aug 15***a.** a finite heat capacity

**b.** an infinite heat capacity

**c.** a finite mass

**d.** none of the above

**ANSWER: an infinite heat capacity**

A thermal energy reservoir has a capacity of absorbing or rejecting an unlimited amount of heat without considerable change in its temperature. These are the large bodies, in which the heat enters or leaves are very slow and very minute. Heat capacity is the product of mass of the body and specific heat of the body. As the thermal energy reservoirs are the large bodies, their heat capacity will be infinite.