Class: JSS 1
Topic: Energy and sources of Energy
What is energy ?
Energy is the capacity of a physical system to do work. There are two main types of energy:
- Potential (Stored)
- Kinetic (Working)
Sources of Energy
Energy can be categorized into:
- Renewable energy
- Non renewable energy
Renewable: These are energy source that can be easily replenished
Nonrenewable: These are energy source that cannot be easily replenished
There are five main renewable energy sources:
- Solar energyfrom the sun
- Geothermal energyfrom heat inside the earth
- Wind energy
- Biomassfrom plants
- Hydropowerfrom flowing water
Examples of energy use:
- When we eat food, our body uses (chemical) energy embodied in the food to move around.
- When we switch on the TV, electricity (kinetic energy) is used to create the picture on the screen and the sound.
- Most of the electricity produced in the world comes from the chemical energy released in the burning of coal, oil or gas.