LAWS OF THERMODYNAMICS

Basically there are four laws of thermodynamics:

zeroth law

first law

it defines light on concept of energy

second law

it defines the limit of converting heat into work and introduces the increase of entropy

third law

it defines the absolute zero of entropy

zeroth law of thermodynamics recognizes that if two systems are in thermal equilibrium with a third, they are also in thermal equilibrium with each other, thus supporting the notions of temperature and heat.

first law of thermodynamics may be expressed by several forms of the fundamental thermodynamic relation:

Increase in internal energy of a system = heat supplied to the system + work done on the system

For a thermodynamic cycle the net heat supplied to the system equals the net work done by the system.

second law of thermo dynamics

Its main import is to tell about irreversibility.

The prime example of irreversibility is in the transfer of heat by conduction or radiation. It was known long before the discovery of the notion of entropy that when two bodies of different temperatures are connected with each other by purely thermal connection, conductive or radiative, then heat always flows from the hotter body to the colder one

Third law of thermodynamics:

The entropy of a substance is zero if the absolute temperature is zero.