Everything has energy

Energy: Definitions, Types, and forms.

Definitions, Types, and Forms of Energy

A glimpse of this post: Energy exists in two types and various forms. Physics defines energy as the capacity of a body to do work while Biology defines energy as the ability to cause change. There two major types of energy: Potential and kinetic energy. The common forms of energy are electrical, mechanical, thermal, chemical, nuclear, sound, radiant, sound, and elastic energy.

Everything is About Energy

Energy has this elementary definition: “Energy is the ability to do work.” Yeah, that’s according to scientists. But it is so broad that there is more to this definition.


The Universe is full of energy. In fact, everything within the universe is all about it.

Everything we see around can be classified as matters because they have mass and occupy space (no matter how little). The matters are in different sizes and shapes. But they have one thing in common: they are built up by building blocks called atoms, which holds a large amount of energy.

For example, the sun. The sun is a huge matter. It holds up lots of energy which it releases through visible light and other forms of electromagnetic rays. When the visible light and other rays (i.e. the carriers of energy from the sun) hits us, we get warmer. That warmth is the effect of the energy from the sun on us, right there.

Another example is the food we eat. Food is a matter that contains energy. When this energy gets combined with the ones in our body, it helps us grow and enable us to make all sorts of movements with our bodies.


In essence, energy is something we can’t see but can feel. It is everywhere, and in everything.

Summary: Everything in the universe contain some form of energy. This is because everything is matters, and matters contain energy.

Energy Definitions in Science

Energy has no general definition that makes sense to everybody, probably because it is a kind of abstract. However, scientists have coined some definitions to help with the understanding of what it is about.

Physics defines energy as the ability or capacity of a system or substance to do work.

Now, you might be asking, ‘What is work?’ Simply, work is the force applied over a distance. Just like, when you apply a force, with your hand, to pull a device from someplace, that’s some work done with your hand, right there.

In other words, it is what makes a body or matter move; it is what causes work to be done. And where would we be, without movement or work, right?


In physics, energy can be equated to be the same as work done. Thus, they have the same standard unit, Joules (J)

Biology defines energy as the ability to cause some kind of change. This is pretty much similar to the Physics definition because for change to occur, there must be movement, and movement is what allows work to be done.

Summary: Physics defines energy as the capacity to get work done while Biology defines energy as the ability to cause some kind of change.

Forms and Types of Energy

There is this misconception about what ‘types’ and ‘forms’ of energy mean. it is so because, in the dictionary, forms and types are synonymous. But, even though they are synonymous, there is still a difference.

‘types’ is used for grouping or classifying while ‘forms’ is for indicating the structure of something

Summary: ‘Types of energy’ is used to classify the various forms of energy.


Types of Energy

Various forms of energy exist. In fact, they are so many that one can’t really know or mention them all. However, according to science, they come in various forms and can all be classified into two types.

Two types of energy:

  • Kinetic energy
  • Potential energy

Kinetic Energy

Simply, kinetic energy is the energy in motion. In more explicit words, it is the energy an object possesses due to its motion. For example, a crawling child, a rolling ball, a falling ball, all possess some form of kinetic energy.

Forms of Kinetic energy

The forms of kinetic energy are:

  • Electrical energy
  • Thermal energy
  • Radiant energy
  • Sound energy

Electrical energy: This is the sort that is derived from the movement of electrons in a conductor or a path. It is this movement of electrons that leads to what we call electricity.

For example, a socket plugged into a wall power outlet could receive electricity and then convert the electrical energy into light energy.


Thermal energy: This can be called heat energy. When a substance or body is heated up (rise in temperature), its molecules and atoms begin to collide and vibrate faster with each other. What results from such a phenomenon is called thermal energy. The faster those molecules or atoms collide, the more heat energy they emit.

For example, heat applied to a pot of water that causes the water to boil and produce heat energy, heat from the sun that increases the temperature of our atmosphere, and so on.

Radiant energy: This is the sort that travels in the form of electromagnetic waves, through space. It is also called light or electromagnetic energy. A common form of radiant energy is solar energy.

Examples are visible light (from the sun, moon, star, light bulb, etc), radio waves, ultraviolet rays, the heat emitted from fire, stove, light bulb, etc, and so on.

Radiant energy travels at a high speed and can either be absorbed, transmitted or reflected. When it can not be absorbed, it gets reflected or transmitted.

Sound energy: This is generated when objects vibrate. It is transferred to our ears in the form of sound waves, through mediums like water and air. For example, when you clap your hands, it produces sound energy; this sound travels through the medium of air, in the form of sound waves, to reach our ear.


Summary: Kinetic energy is the energy of a body in motion. Examples of kinetic energy are electrical energy, thermal energy, radiant energy, and sound energy.

Potential Energy

Simply, this is the energy in position. It is the sort that is contained in an object or body in relation to other objects or factors. For example, food, a stretched spring, an object placed on a height, all contain some form of potential energy.

Forms of Potential Energy

The forms of potential energy are:

  • Chemical energy
  • Nuclear energy
  • Gravitational energy
  • Elastic energy

Chemical energy: This is one that is stored in the bond of chemical compounds. It is one that holds the chemical compounds together. And it can only be released when it undergoes a chemical reaction.

For example, the food we eat has chemical energy stored in them; and when we consume them, it goes through chemical reactions, thereby releasing the chemical energy to our body. This is what helps you grow, move and do all other sorts. Other examples are the chemical energy contained in natural gas, petroleum, wood, biomass, coal and so on.

Nuclear energy: This is defined as one that is stored in the nucleus of atoms. And It can be released when the atom that contains it goes through nuclear reactions (Nuclear fission or fusion).


For example, Uranium is one raw material that contains huge nuclear energy. For it to be released, it will have to go through a chain reaction (Fission). It is this chain reaction that releases it in the form of heat energy.

Gravitation energy: This is one that has an association with gravity. When a mass or body is placed in a position where it can get pulled by gravitation force, it is said to possess gravitational energy.

For Example, a book placed at a height possesses gravitation energy. When the book gets released, the gravitational force pulls it down. At the ground level, gravitation energy possessed by the book becomes zero. The greater the mass of the book at a height, the more gravitational force acts on it, and the more the gravitational energy it possesses.

Elastic energy: This is the form that is stored when an object is temporarily deformed and is released when the object goes to its original shape.

For example, when you pull a catapult, it stretches and possesses the elastic energy, but when released, it goes back to its original shape with zero elastic energy. Other examples are a stretched bow, a stretched rubber band, a compressed ball that goes back to its original shape when released, etc.

Summary: Potential energy is the energy that is contained in a body due to its position in relation to other objects or factors. Examples of potential energy are chemical energy, elastic energy, gravitational energy, and nuclear energy.


Kinetic and potential Energy (Hybrid)

Mechanical (motion) energy is sometimes classified as a form of kinetic energy, but it can actually be the sum of kinetic and potential energy. So, you might want to call it a hybrid.

For example, when you kick a ball, your leg moves. Your leg contains potential energy, and this will combine with the kinetic movement of your leg to kick the ball.

Also, when you open a door with your hand, mechanical energy is in play because you combine the potential energy of your hand and the kinetic movement of your hand to open the door. Other examples are hitting a nail with a hammer and more

Energy will always play a major role in the lives of living and non-living bodies in the universe. It is what binds everything together, and allows work to be done.In fact, it can be related to invisible entities like vibes.

Summary: Mechanical energy is the sum of kinetic and potential energy.

Frequently Asked Questions

What are the 9 forms of energy?

Electrical, mechanical, heat, elastic, gravitational, nuclear, sound, radiant, and chemical energy.

What is the other name for stored energy?

Stored energy is also called potential energy. Potential energy is energy stored in an object or substance.

What is the simple definition of energy

Energy is the ability or capacity to do work.

What are the 4 main forms of kinetic energy?

The four main forms of kinetic energy are electrical, thermal, radiant and sound energy.

What are the forms of potential energy

The four main forms of kinetic energy are Chemical, nuclear, gravitational and elastic energy.

Is mechanical kinetic or potential energy?

Mechanical energy can be potential energy, kinetic energy or both

Is gravity a type or of energy?

Gravity is what causes a form of potential energy called gravitational energy.


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