Energy Basics Various Forms of Energy Conservation of Energy
Definition of Energy
Energy is the ability to do work and work is the transfer of energy from one form to another. In practical terms, energy is what we use to manipulate the world around us, whether by exciting our muscles, using electricity or using mechanical devices such as automobiles.
Energy comes in different forms – heat (thermal), light (radiant), mechanical, electrical, chemical and nuclear energy.
Various forms of energy
There are two types of energy – stored energy (potential) and work energy (kinetic).
For example, the foods we eat contain chemical energy, and our bodies store that energy until we release it when we work or play.
1) Potential Energy
Potential energy is stored energy and position (gravitational) energy. It exists in several forms.
2) Chemical Energy
Chemical energy is the energy stored in the bonds of atoms and molecules. Biomass, oil, natural gas, propane, and coal are examples of stored chemical energy.
3) Nuclear Energy
Nuclear energy is the energy stored in the nucleus of an atom – the energy that holds the nucleus together.
The nucleus of a uranium atom is an example of nuclear energy.
4) Stored Mechanical Energy
Stored mechanical energy is the energy stored in objects by the application of a force. Compressed springs and stretched rubber bands are examples of stored mechanical energy.
5) Gravitational Energy
Gravitational energy is the energy of place or position. Water in a reservoir behind a hydroelectric dam is an example of gravitational energy. When water is released to turn the turbines, it becomes energy of motion.
6) Kinetic Energy
Kinetic energy is energy in motion – the movement of waves, electrons, atoms, molecules and substances. It exists in several forms.
7) Radiant Energy
Radiant energy is electromagnetic energy that travels in transverse waves. Radiant energy includes visible light, X-rays, gamma rays and radio waves. Solar energy is an example of radiant energy.
8) Thermal Energy
Thermal energy (or heat) is the internal energy of substances – the vibration and movement of atoms and molecules within substances. Geothermal energy is an example of thermal energy.
9) Movement
The movement of objects or substances from one place to another is movement. Wind and hydroelectric energy are examples of movement.
10) Sound
Sound is the movement of energy through substances in longitudinal waves (compression/rarefaction).
11) Electrical Energy
Electrical energy is the movement of electrons. Lightning and electricity are examples of electrical energy.
Energy Conversion
Energy is defined as “the ability to do work”. In this sense, examples of work include moving something, lifting something, heating something, or lighting something.
The following is an example of the transformation of different types of energy into heat and energy.
It's hard to imagine going through an entire day without wasting energy. We use energy to light our cities and homes, to power machines in factories, to cook our food, to play music and to operate our televisions.
