Energy is defined as the capacity to do work. The various forms of energy can be classified as:
• Mechanical (kinetic and potential)
• Radiant (electromagnetic)
• Chemical (potential)
In the following sections, we will discuss each of the above-mentioned forms of energy.
Mechanical energy includes both kinetic and potential energy. Friction is related to mechanical energy as it is caused by kinetic energy and the potential energy of a body as a force is applied through a distance.
Heat energy is the energy a body possesses because of its internal energy due to the motion of the particles it contains.
Radiant energy is the source of all life on the Earth and is the greatest potential energy resource available for the future.
When radiant energy in the form of light is absorbed by plants, it is converted into stored chemical energy. This energy is available as food or biomass. Biomass is used to produce fuels.
Radiant energy is electromagnetic in nature and is possessed by all components of the electromagnetic spectrum (γ–rays, X–rays, UV radiation, visible light, IR radiation, microwaves, and radio waves). Infra-red radiation falling on a body is converted into thermal energy.
Solar energy is a form of radiant energy.
Chemical energy is the energy locked up in fuels and other chemicals.
The energy obtained by the combustion of fuels represents a major source of energy in current use.
All food that we eat is a store of chemical energy. It can be considered to be latent potential energy that a body possesses.
Sound energy is produced by longitudinal waves that have an organized and periodic pattern that causes the vibration of the particles in the same direction as the transfer of energy.
Electrical energy is the energy carried by moving charges and these moving charges produce a magnetic field.
Through the process of electromagnetic induction, electricity has become the greatest form of energy used by man in everyday life.
Nuclear energy is the potential binding energy released during a nuclear reaction when mass is converted to thermal and perhaps light energy.
Nuclear fission reactors are starting to gain renewed acceptance and nuclear fusion has potential for the future when the technology becomes available.