Question

What is Steady State and Thermal Equilibrium?

Answer 1

Steady-state:

• A steady-state is a condition or a state in which all variable remains constant and does not change with time despite continuous activity which tries to alter them.
• Example: A bathtub with the tap running but the drain unplugged: After a given amount of time, the water level stabilizes and the system is in a steady state.

Thermal equilibrium:

• Any two systems remain in thermal equilibrium when there is no flow of heat takes place between them. i.e. in thermal equilibrium change in heat is zero as there is no flow of heat takes place and both the systems are present at same temperature.
• As we know, the flow of heat occurs from higher temperature to the lower temperature also called a temperature gradient. Therefore, two systems are considered in a thermal equilibrium when they both are present at same temperature so, that no heat exchange can be occur.
• Thermal equilibrium is governed by the zeroth law of thermodynamics.