Energy is the ability or capacity to do work. Every activity that occurs around us requires energy. There are many forms or types of energy, and each one is useful in different ways. These types of energy can change from one form to another, but the total energy remains constant.

Below are the major types of energy taught in Basic Science for Junior Secondary School in Nigeria:

1. Mechanical Energy



Mechanical energy is the energy a body possesses due to its motion or position. It has two parts:

a) Kinetic Energy

This is the energy a body has because it is moving.

Examples:

1. A running boy


2. A moving car


3. A flowing river



b) Potential Energy

This is stored energy that a body has because of its position or shape.

Examples:

1. Water stored in a tank


2. A book placed on a shelf


3. A stretched rubber band



Mechanical energy = Potential Energy + Kinetic Energy.

2. Chemical Energy



Chemical energy is the energy stored inside substances. This energy is released during chemical reactions.

Examples:

1. Food contains chemical energy that the body uses


2. Petrol and diesel release chemical energy when burnt


3. Batteries store chemical energy and release it when used


3. Heat Energy (Thermal Energy)



Heat energy is the energy that causes objects to become warm or hot.

Heat energy can be produced through:

1. Burning


2. Friction (rubbing two things together)


3. Electricity



Examples:

1. The heat from the sun


2. The heat from a cooker


3. Ironing clothes


4. Light Energy



Light energy is the energy that enables us to see.

Sources of light include:

1. The sun (the major natural source)


2. Electric bulbs


3. Candles


4. Fire



Plants use light energy from the sun to make food through photosynthesis.

5. Sound Energy



Sound energy is produced when objects vibrate.

Examples:

1. Sound from radios


2. Talking or singing


3. Beating a drum



Sound helps us to communicate and to hear what is happening around us.

6. Electrical Energy



Electrical energy is the energy caused by the movement of electric charges. It is very useful because it can easily be changed into other forms, such as light, heat, and sound.

Examples:

1. Electricity in homes and schools


2. Electric fans


3. Freezers and refrigerators


4. Televisions


7. Solar Energy



Solar energy is energy from the sun. It is a natural and renewable form of energy.

Examples:

1. Solar panels


2. Drying clothes in the sun


3. Solar water heaters


8. Nuclear Energy



Nuclear energy is the energy released from the nucleus of atoms. It comes from nuclear reactions like fission and fusion. Although not common in Nigeria, it is used in some countries to generate electricity.

9. Elastic Energy



Elastic energy is the energy stored in objects that can stretch or compress.

Examples:

1. A stretched spring


2. A stretched rubber band


3. A bow before shooting an arrow


10. Magnetic Energy



Magnetic energy is the energy stored in magnets and magnetic fields.

Examples:

1. Magnets used to pick up metal objects


2. Magnetic strips on ATM cards


3. Door magnets in refrigerators

1. Renewable Energy



Renewable energy comes from natural sources that can be replaced or replenished within a short period of time. These sources do not run out easily because nature constantly renews them.

Examples:

1. Solar energy (from the sun)


2. Wind energy


3. Water or hydro energy


4. Biomass (from plants and animals)


5. Geothermal energy (heat from beneath the earth)



Key Features:

1. Clean and environmentally friendly


2. Will not get exhausted


3. Can be used repeatedly


2. Non-renewable Energy



Non-renewable energy comes from sources that cannot be replaced quickly. Once they are used up, they take millions of years to form again. These resources are limited and can eventually run out.

Examples:

1. Crude oil (petroleum)


2. Coal


3. Natural gas


4. Nuclear fuel (uranium)



Key Features:

1. They cause pollution when used


2. They are limited in supply


3. They may become very expensive when scarce

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Summary

Energy is the ability to do work and exists in many forms such as mechanical, chemical, heat, light, sound, and electrical energy.

Each type of energy has a unique source and use, but they can all change from one form to another.

The total amount of energy remains constant because energy cannot be created or destroyed.