### First Law Of Thermodynamics

**Definition:**The

**is the application of the conservation of energy. Energy is neither be create or not be destroyed. The total amount of energy of the earth is a constant. The energy can be transferred from one form to another form.**

*first low of thermodynamics*The 1st law of thermodynamics can be mathematically stated as follows:

§dQ = §dW

In Thermodynamic Cycle, a cyclic process the systems undergoes, the cyclic integral of heat added is equal to integral of work done. The first law equation can be written in the form,

§(dQ – dW) = 0

**First Law Of Thermodynamics Equation**

Equation dU = dQ – dW is a corollary to the first law of thermodynamics. It shows that there exists a property internal energy (U) of the system, such that a change in its value is equal to the difference in heat entering and work leaving the system.

**Also Read:**

The sign convention for heat and work in the first law of thermodynamics is represented in the picture below.