First and Second Laws of Thermodynamics

The first law of thermodynamics, also known as the law of energy conservationThe professional care, preservation, and restoration of archaeological materials and sites, often requiring scientific expertise., states that energy cannot be created or destroyed, but it can be converted from one form to another. In terms of thermodynamics, energy is usually classified into two main types: internal energyTotal kinetic and potential energy of all particles within a system., which represents the total energy of the atoms and molecules within a substance, and external energy, which represents the energy that is exchanged between a system and its surroundings. The first law can be stated mathematically as the change in internal energy of a system is equal to the heat added to the system minus the work done by the system.

The second law of thermodynamics, also known as the law of entropyAn indicator of the physical disorder of a system., states that heat cannot be completely converted into work, and that there is always some waste heat produced in any energy conversionThe act of changing someone's religion. process. The second law is based on the concept of entropy, which is a measure of the disorder or randomness of a system. In thermodynamics, the second law is often used to determine the maximum theoretical efficiency of a heat engine, which is a device that converts heat into work.