Question

What is the zeroth law of thermodynamics ?

Answer 1

The definition of temperature as an indicator of thermal equilibrium is framed by the zeroth law of thermodynamics. The first of the four laws of thermodynamics is the zeroth law. Ralph H. Fowler deserves credit for coming up with the rule.

Complete answer:
The zeroth law of thermodynamics states that if two thermodynamic systems are in thermal equilibrium with a third system, they are in thermal equilibrium with one another.When two systems are connected by a wall permeable only to heat and do not shift over time, they are said to be in thermal equilibrium. In a nutshell, systems are said to be in a thermal equilibrium relationship if they are not linked in such a way that they can transfer heat to one another, but would also not do so if they were bound by a heat-permeable wall.

For example: Suppose there are three bodies ‘X’, ‘Y’ and ‘Z’. If ‘X’ is in thermal equilibrium with ‘Y’ and ‘X’ is in thermal equilibrium with ‘Z’ also at the same time, then according to Zeroth law of thermodynamics, ‘Y’ and ‘Z’ are in thermal equilibrium with each other.

Note: Law tells that temperature is a worthwhile measurement since it predicts whether or not heat can pass between items. The radiation mode of heat transfer allows heat to flow between two objects even though they are not physically in contact.Meanwhile, the zeroth law of thermodynamics states that no heat flow will occur if the systems are in thermal equilibrium.