HEAT

A. Introduction

1. Heat is a form of energy.

2. Heat cannot be seen but can be felt.

B. Sources of Heat

1. The Sun is our main source of heat.

2. All living things on Earth need heat to survive.

3. Our Sources of heat are from:

(a) The Earth
(b) Electricity
(c) Chemical reactions
(d) Fiction
(e) Nuclear energy

4. When a volcano erupts, some of the heat beneath the ground escapes to the Earth's surface.

5. A geyser is a spring that spurts up hot water with a great force from time to time.

6. Heat energy that comes from the ground is known as geothermal energy.

7. Man uses geothermal energy to produce electricity.

8. Chemical reactions like oxidation, combustion and decomposition produce heat.

9. Decomposition happens when a substanec breaks down into two or more simpler substances.

10. Combustion happens when a fuel reacts with the oxygen in the air giving off heat and light.

11. Fiction is produced when one object or surface rubs against another.

12. Electricity can be passed through certain metals and other materials to produce heat.