Concept of Energy Conversion

Class: Basic 5

Subject: Basic Science and Technology

Topic: Concept of Energy Conversion.

Energy exists in various forms. Some of these forms are:

I.) Mechanical energy

II.) Chemical energy

III.) Light energy

IV.) Electrical energy

V.) Heat energy

VI.) Nuclear energy

VII.) Solar energy

VIII.) Wind energy

Energy can be changed from one form to another. The two forms of energy from the sun are light and heat energy. They exist naturally and can be used directly.

Other forms do not occur naturally and have to be obtained by conversion from other types. For example, electrical energy has to be obtained by conversion from chemical, mechanical or heat energy.

Solar energy gets to the earth as light and heat energy. Plants trap the light energy and convert it to Chemical energy. The chemical energy in plant is taken by man and is converted to mechanical energy.

Solar energy can be converted directly to electrical energy using solar cells.

In another way, energy from sun helps in the formation of the water cycle. We take advantage of the water cycle to generate electricity (electrical energy). The electrical energy is then converted to light and heat energy.

Wind energy is converted by windmill device to mechanical energy, which is used to grind maize, wheat or some other items.

The energy changes that take place in a torchlight is chemical energy (dry cell) to electrical energy to light energy.

Review questions:

1) What is energy?

2) List five forms of energy

3) When batteries are used in a torchlight, which energy conversions have taken place?

4) Solar energy can be converted directly to _______________________ using _________________.