Thermal Physics

1. Department of Physics
Topic –Zeroth Law of thermodynamics
Prof. B.V. Tupte
Head, Department of Physics
Shri Govindrao Munghate Arts and
Science College Kurkheda.

2.  Every system in this universe spontaneously move
towards equilibrium.
 If a thermodynamic system shows no tendency to
change its properties with time it is said to be in a
state of thermal equilibrium
Thermal equilibrium refers to equality of
temperatures.
Thermal equilibrium is the subject of the
Temperature measurement.

3.  If two systems are in thermal equilibrium with a third system,
they must be in thermal equilibrium with each other.
 Statement :- The Zeroth law of thermodynamics states that if two
bodies A and B are each separately in thermal equilibrium with a
third body C, then A and B are also in thermal equilibrium with
each other .
 Practically this means that all three are at the same temperature.
 A basis for comparison of effect of temperatures.