What is Energy? Work, Energy and Power.
- The energy of a body is defined as its capacity for doing work.
- Since energy of a body is the total quantity of work done therefore it is a scalar quantity.
- Mass energy equivalence : Einstein’s special theory of relativity shows that material particle itself is a form of energy. The relation between the mass of a particle m and its equivalent energy is given as
- Annihilation of matter when an electron and a positron combine with each other, they annihilate or destroy each other. The masses of electron and positron are converted into energy. This energy is released in the form of -gamma rays.
- Nuclear bomb : When the nucleus is split up due to mass defect (The difference in the mass of nucleons and the nucleus) energy is released in the form of gamma-radiations and heat.
- Various forms of energy
- Mechanical energy
- (Kinetic and Potential)
- Chemical energy
- Electrical energy
- Magnetic energy
- Nuclear energy
- Sound energy
- Light energy
- Heat energy
Transformation of energy :