Page 32 - Science and Technology Std 3

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Heat transfer methods
Heat always moves from a warm to a cool place. For example,
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hot objects in a cool room will cool to a room temperature.
Also, cold objects in a warm room will heat up to the room

temperature.

Three ways of heat transfer
1. Conduction is the transfer of heat through solid objects.

When a metal strip is heated at an end, the
heat travels to the other end.

2. Convection is the transfer of heat through liquid substances

such as water.

3. Radiation is the transfer of heat through the air.

Look at the following pictures to study different uses of heat.

a Warming

ourselves during

cold weather

b Ironing clothes

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PROPERTY OF UNITED REPUBLIC OF TANZANIA GOVERNMENT
Ministry of Education, Science and Technology
Science and Technology 3.indd 25 03/08/2019 11:01