Energy is the ability to do work. Energy is a conserved quantity and the SI unit of energy is Joule. Energy exists in different forms.
Law of conservation of energy
The law of conservation of energy is one of the fundamental laws in physics. It directs the microscopic motion of individual atoms in a chemical reaction. The law of conservation of energy states that energy can neither be created nor destroyed but can only be converted from one form to another. According to the law of conservation of energy, the total energy of an isolated system remains conserved over time.
Listed below are few examples of the law of conservation of energy
- In a loudspeaker, electrical energy is converted into sound energy.
- In a microphone, sound energy is converted into electrical energy.
- The sun’s radiation or heat is used in solar panel and cells and is converted to electrical energy.
- The mechanical energy of the windmill to rotate the shafts in the windmill is converted to electrical energy.