Heat Reservoir, Source and Sink

 The ideal body having large thermal energy capacity which either continuously supplies or absorbs the infinite amount of heat without changing its temperature is called thermal energy reservoir or heat reservoir.

HEAT RESERVOIR, SOURCE AND SINK

The ideal body having large thermal energy capacity which either continuously supplies or absorbs the infinite amount of heat without changing its temperature is called thermal energy reservoir or heat reservoir.

If the reservoir continuously supplies heat energy to the system, it is called a source or hot reservoir. The source is always at high temperature. If the reservoir continuously absorbs heat energy from the system, it is called a sink. The sink is always at low temperature or cold reservoir.