state and apply two energy laws to energy transformations

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gsenviro | College Teacher | (Level 1) Educator Emeritus

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The two energy laws are actually laws of thermodynamics. The first law is also known as the law of conservation of energy. In simplest terms, it states that energy can neither be created nor be destroyed, it may simply change from one form to another and the total amount of energy in the universe remains constant. In thermodynamics terms, it simply means that the net internal energy change of a system is the sum of work done by (or upon) it and heat energy added to it. The second law states that the entropy of the universe always increases. Entropy can also be thought of as useless energy. 

Lets look at how these laws are applicable. Consider what happens when we drive a car. The chemical energy available in the gasoline (or petrol) is converted to heat energy by combustion. This heat energy is used to push the vehicle forward. However, most the energy is lost as heat and the actual efficiency of the engine is very low. Similarly, hydroelectric power is based on conversion of potential energy of water to the electricity by action of turbines. Here as well, we see some loss of potential energy of water and this loss is not converted to electricity.

Hence conversion of energy from one form to another and loss of useful energy is each energetic process are examples of two laws of energy.

Hope this helps.

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