What is the zeroth law of thermodynamics?

Problem Statement

What is the zeroth law of thermodynamics?

Step-by-Step Explanation

The zeroth law says that if two systems are each in thermal equilibrium with a third, they are in thermal equilibrium with each other.

1. Identify what the question is asking. In Thermodynamics, this usually means naming the known quantities, the unknown quantity, and the concept that connects them.
2. Write the relevant definition, rule, or relationship before substituting numbers or manipulating symbols.
3. Work one step at a time and keep units, signs, and restrictions visible.
4. Check whether the answer makes sense in the original context.

Final Answer

The zeroth law says that if two systems are each in thermal equilibrium with a third, they are in thermal equilibrium with each other. The reliable strategy is to start from the definition, apply the correct rule carefully, and then interpret the result in plain language.