Thermal Equilibrium
When there is no transfer of heat between two bodies in contact , the the bodies are called in thermal equilibrium .
Zeroth Law of Thermodynamics
If two bodies A and B are separately in thermal equilibrium with thirtli body C , then bodies A and B will be in thermal equilibrium with each other .
Triple Point of Water
The values of pressure and temperature at which water coexists inequilibrium in all three states of matter , i . e ., ice , water and vapour called triple point of water .
Triple point of water is 273 K temperature and 0.46 cm of mere pressure . Specific Heat
The amount of heat required to raise the temperature of unit mass the substance through 1 ° C is called its specific heat .
It is denoted by c or s .
Its SI unit is joule / kilogram- ° C '( J / kg- ° C ). Its dimensions is [ L 2 T -2 θ -1 ].
The specific heat of water is 4200 J kg -1 ° C -1 or 1 cal g -1 C -1 , which high compared with most other substances .
Gases have two types of specific heat 1 . The specific heat capacity at constant volume ( Cv ). 2 . The specific heat capacity at constant pressure ( Cr ).
Specific heat at constant pressure ( Cp ) is greater than specific heat constant volume ( CV ), i . e ., Cp > CV .
For molar specific heats Cp – CV = R where R = gas constant and this relation is called Mayer ’ s formula .
The ratio of two principal sepecific heats of a gas is represented by γ .