What is Thermodynamics? Explain the Zeroth law of Thermodynamics and give its importance.

Question

Filo · Accepted Answer

It is based on the principle of temperature.
To understand this law, consider two systems

A

and

B

, separated by an adiabatic wall, each of these are in contact with a third system

C

by a conducting wall. The states of the system will change until

A

and

B

are in equilibrium with

C

. Now, let the adiabatic wall between

A

and

B

be replaced by a conducting wall and

C

is insulated from

A

and

B

by an adiabatic wall. It is found that

A

and

B

are in thermal equilibrium with each other. This is the basis of Zeroth law of thermodynamics. This law states that the two systems are in thermal equilibrium with a third system separately, then both are in thermal equilibrium with each other.
The zeroth law apparently suggests that when two systems

A

and

B

are in thermal equilibrium, then , there must be a physical quantity that has the same value for both. The thermodynamic variable whose value is equal for the two systems (in thermal equilibrium) is called temperature