# Types of Energy

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Introduction

Energy is the scalar quantity whose SI unit is given in "Joule." Energy is found in various things, and therefore there are different types of energy. All energy forms are either potential (energy that is stored) or kinetic (the energy of moving objects). It can be changed from one to another type, but it can be neither destroyed nor created.

This is something we have heard a hundred times from our teacher, but if we have asked what kind of work has to be accomplished to define the term energy, we can define it like this. Work is said to be accomplished, when an object is moved against a force, such as gravity.

Different Forms of Energy

There are many different kinds of energy, which fall into two primary forms: potential and kinetic. Let us have a look at different forms of energy and examples.

• Kinetic Energy

Kinetic energy can be defined as the energy of motion. If an object is in a moving state, it is said to have kinetic energy. Kinetic energy is one of the two primary energy forms - the other is the potential (so-called stored) energy. For example, flowing water, a moving ball, and more.

The kinetic energy equation can be given by, ½ m x v²

Where v is the object velocity, and m is the object mass.

• Potential Energy

Potential energy is the kind of energy stored within an object because of its arrangement, position, or state. This energy is one of the two primary forms of energy, along with kinetic energy.

It is measured by the amount of work done. A few examples are water in a lake, a pen on the table, and more.

The potential energy equation can be given by, m x g x h

Where ‘m’ is the mass of the object in kilograms, ‘g’ is the acceleration due to gravity, and ‘h’ is the height in metres.

• Mechanical Energy

The sum of potential and kinetic energy that is associated with the motion & the position of an object is called Mechanical energy. Therefore, we can derive the formula of mechanical energy as:

Mechanical Energy = Kinetic Energy + Potential Energy,

Mechanical energy = ½ m x v² + mgh

• Chemical Energy

It is the energy that is stored in chemical compound bonds, such as molecules and atoms. In the same environment and given temperature, energy can either be released or absorbed due to the reaction between the set of chemical substances is equal to the difference between reactants and energy content of the products. When a chemical reaction takes place, this energy is released.

Once chemical energy has been released from a substance, usually, that substance then transformed into a new substance completely.

Some other types of energy are Magnetic, Electric, Nuclear, Radiant, Elastic, Ionization, Thermal, Gravitational, and Heat & Mechanical work. Chemical energy can also be used in food and wood and stored in Biomass, Coal, Chemical batteries, and vehicle's airbags.

• Light Energy

Light energy is a kind of electromagnetic radiation. Light consists of photons that are produced when the atoms of an object heat up. Light travels in waves, and it is the only form of energy visible to the human eye. This type of energy is also kinetic energy.

Light is made of photons, which are tiny packets of energy. When the atoms of an object heat up, photons are produced from the movement of atoms. The photons are produced depending on the heat of the object.

• Heat or Thermal Energy

Thermal energy can also be called heat energy, which is produced when a rise in temperature causes molecules and atoms to move faster and collide with each other.

The energy that comes from the temperature of the heated substance is known as thermal energy.

Some examples of thermal energy are the warmth from the sun, A cup of hot chocolate, Baking in an oven, and the heat from a heater.

The below representation of boiling water on a stove shows the example of thermal energy.

These are some of the energy forms and in addition to these, there are various forms of energy.

Different Types of Energy Resources

Energy sources are also used as fuels. These fuels are used in automobiles, machinery, and many other industries. They are used in the thermal plants to generate electricity. Energy resources can be further classified into two types as Non-renewable and Renewable. The types of energy sources are given below.

• Non-renewable Resources

Fossil fuels like natural gas, oil, and coal are called non-renewable energy resources because if these are used once, they cannot be renewed by natural processes or any means.

• Renewable Resources

Natural resources like water, wind, geothermal, and solar are known as the types of renewable energy sources as they come from the sources that regenerate it back after consumption and are available in nature continuously.

Some energy types based on their resources are given below.

• Coal

• Bioenergy

• Geothermal

• Hydropower

• Hydrogen

• Nuclear

• Natural Gas

• Oil

• Solar

• Wood

• Wind

As we may have guessed, gravitational energy is the energy associated with gravity. It is the type of potential energy stored by an object due to its higher position than that of a lower position. (for example, if it's further away or closer to the ground).

Gravitational energy is the energy associated with gravity - the representation given below shows that gravitational energy is also used to propel the ride along the tracks.

Systems can also increase the gravitational energy as mass moves away from the centre of the Earth or other objects that stay large enough to produce significant amounts of gravity like the planets, Sun, and the stars.

2. Where Did the Energy Come From?

As per the law of conservation of energy, "Energy neither be created, nor be destroyed, but it can be changed from one standard form to another."

The energy we are using is simply the conversion of other forms. It has no particular sources. However, most of the energy which we used is the result or product of the Sun.