What is Energy?

What is energy? According to experts, energy is the ability to perform work. Studies have shown that it is possible to transfer energy from one medium to another and use it to perform tasks that allow the way of life to exist. Walking, cooking, driving, and other daily activities all require an amount of energy.

Energy is required for all living things and the processes that happen throughout the universe. The sun is the most important source of energy for living things on Earth. Solar energy is available actively in the form of photosynthesis and passively in the form of carbon energy. 

Definition of energy

Energy is a fundamental natural entity transferred between parts of a system to produce a significant reaction within the system. 

The energy of a substance is an attribute that results from its atoms, molecules, or combined formulations. Since a chemical progression is associated with a transition within some structures mentioned above, there can be variation in the total existing energy, which is generally less but increases in rare cases. Some power may be redistributed among the environment and the intermediate products in the form of heat produced or illumination. Outcomes of a transformation may also contain a greater amount of energy when compared to reactants, but this is not always the case.

Characteristics of energy

The three fundamental characteristics of energy are:

1. The ability to cause an object to transform or perform tasks
2. The energy that an entity has when it’s still moving
3. The energy that an entity has when it is standing still

The different forms of energy are:

• Heat
• Light
• Movement
• Electricity
• Chemical-based
• Gravity

Depending on the type of energy consumed, energy can be expressed in different measurement units. They are as follows:

Different measurement units of energy

Law of conservation of energy

According to the law of conservation of energy, energy cannot be created nor destroyed; it can only be transformed from one form of energy to another. For example, from petrol to the combustion engine of a car. It means that until energy is applied from elsewhere, a framework will invariably have the exact energy unit. This is especially puzzling in the case of non-conservative forces, in which, energy is transformed from mechanical to thermal power while the overall energy remains constant. Energy can only be used by converting it from one form to another.

Therefore, the quantity of energy in any framework is calculated using the formula:

KE = 0.5 m v²

Types of energy

There are various types of energy. However, energy is broadly categorised into two types: 

1. Potential energy: the energy that an entity has when it is standing still and can manifest due to its proximity and status.
2. Kinetic energy: the energy that an entity has when it is moving.

A bullet loaded in a gun has energy stored in it, which is there because of its position and composition. When the same bullet is fired from the gun, it possesses kinetic energy owing to its movement.

When energy from one source is applied to another, there is a definite transformation of energy into another form. For example, solar panels absorb sunlight and transform it into electricity that can be used for various purposes. Another example is how jet fuel (chemical energy) in an aeroplane is applied to produce mechanical energy for flight.

Sources of energy

Solar energy, the energy that we receive from the sun, is the biggest source of energy found all around us. The process of generation of energy from the sun is known as Nuclear Fusion.

Other primary sources of energy and their applications:

• Coal –  Electricity and Manufacturing Industries
• Wood – Heat, Electrical, and Transportation
• Wind – Electricity
• Water – Electricity

Secondary sources of energy and their applications:

• Food – Human Energy
• Electricity – Power

Apart from the above categories, energy sources are also distinguished as Conventional and Non-Conventional sources of energy.

Conclusion:

Understanding the various forms of energy and its applications makes it apparent how vital energy is for the existence of human beings. Each activity that a human being does involves the application of energy in one form or the other. After understanding the importance of energy, efforts are being taken to conserve energy and understand concepts of energy efficiency. An example of which is the star ratings on energy appliances, which highlight the energy efficiency of appliances. Another example is the adoption of electric vehicles.