How many forms of energy are there? (Review)

We use energy to cook foods, to make ice, to move cars along roads, and boats throng water. But are we all know exactly what energy is and how many forms of energy around us? Let’s discuss about this.

Scientists define energy as the ability to do work and nowadays, human have learned how to change energy from one form to another for many different purposes.

So the question is how many forms of energy and what are they?

We separate forms of energy into two basic categories:

  • Potential energy
  • Kinetic energy

1. Potential energy:

Potential energy is stored energy and the energy of position.

1.1. Chemical energy is energy stored in the bonds of atoms and molecules. Batteries, biomass, petroleum, natural gas, and coal are examples of chemical energy. When people burn wood in a fireplace or burn gasoline in a car's engine, Chemical energy is converted to thermal energy.

You can see more cool stories about energy at: 17 energy technology of the future

1.2. Mechanical energy is energy stored in objects by tension. Compressed springs and stretched rubber bands are examples of stored mechanical energy.

Examples: Striking a match, combining vinegar and baking soda to form CO2 Gas, breaking light sticks releases chemical energy.

1.3. Nuclear energy is energy stored in the nucleus of an atom-the energy that holds the nucleus together. Plenty amounts of energy can be released when the nuclei are combined or split apart.

1.4. Gravitational energy is energy stored in an object's height. The higher and heavier the object, the more gravitational energy is stored. When people ride a bicycle down a steep hill and pick up speed, the gravitational energy is converting to motion energy. Hydropower is another example of gravitational energy, where gravity forces water down through a hydroelectric turbine to produce electricity.

1.5. Elastic energy can be stored mechanically in a compressed gas or liquid, a coiled spring, or a stretched elastic band. On an atomic scale, the stored energy is a temporary strain placed on the bonds between atoms, meaning there’s no permanent change to the material. These bonds absorb energy as they are stressed, and release that energy as they relax.

2. Kinetic energy:

Kinetic energy is the motion of waves, electrons, atoms, molecules, substances, and objects.

2.1. Radiant energy is electromagnetic energy that travels in transverse waves. Radiant energy includes visible light, x-rays, gamma rays, and radio waves. Light is one type of radiant energy. Sunshine is radiant energy, which provides the fuel and warmth for possibility of life on earth. Radiant energy can be converted to the chemical energy stored in plants through photosynthesis, the process by which plants and algae use the sun’s radiation to turn carbon dioxide gas into sugar and carbohydrates.

2.2. Thermal energy or heat, is the energy that comes from the movement of atoms and molecules in a substance. Heat increases with increases in the speed that these particles move. Geothermal energy is the thermal energy in the earth. We can’t see individual atoms vibrating, but we can feel their kinetic energies as temperature. When there’s a difference between the temperature of the environment and a system within it, thermal energy is transferred between them as heat.

2.3. Motion energy is energy stored in the movement of objects. The faster they move, the more energy is stored. It takes energy to get an object moving, and energy is released when an object slows down. An example of motion energy is a car crash. When a car comes to a total stop and releases all of its motion energy at once in an uncontrolled instant.

2.4. Sound is the movement of energy through substances in longitudinal (compression/rarefaction) waves. Sound is produced when a force causes an object or substance to vibrate. The energy is transferred through the substance in a wave. Typically, the energy in sound is smaller than in other forms of energy.

Examples: Voices, whistles, horns and musical instruments.

2.5. Electrical energy is delivered by tiny charged particles called electrons, typically moving through a wire. Lightning is an example of electrical energy in nature.