# First Law Of Thermodynamics

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First law of thermodynamics state that internal energy is a function of state and the increase in internal energy is equal to the sum of the heat supplied to system and work done on system.

$\Delta U \, = \, Q + W$

$\Delta U$ is the increase in internal energy(U) of system,

Q is the heat supplied to the system,

W is the work done on the system.