yr9 - conduction and insulators

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Dr Pusey www.puseyscience.com Why do bathroom tiles feel cold when you step on them compared to carpet? What is happening to the heat in the above situation?

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Page 1: Yr9 - conduction and insulators

Dr Pusey

www.puseyscience.com

Why do bathroom tiles feel cold when you step on them compared to carpet?

What is happening to the heat in the above situation?

Page 2: Yr9 - conduction and insulators

Recap - Heat Heat is the transfer of energy from one point of high

temperature to a point of low energy.

The greater the temperature difference, the faster the heat flows from one object to the other.

Heat is transferred from one area to another in three ways: Conduction

Convection

Radiation

Page 3: Yr9 - conduction and insulators

Conduction Hot particles in hot substances

move faster These excited particles bounce

into other particles and make them excited (vibrate faster)

The cooler particles also gain kinetic energy as heat is conducted through them.

And so it goes on

Page 4: Yr9 - conduction and insulators

Heat Conductors Some substances are excellent

conductors of heat. These include: Metals such as copper and aluminium

Heat flows easily through heat conductors.

When holding a piece of metal, it feels cold because heat is easily transferred from your hand to the metal.

When holding a poor conductor, heat is not transferred through the substance and therefore it does not feel cold.

Page 5: Yr9 - conduction and insulators
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On railway lines

Page 8: Yr9 - conduction and insulators

Heat Insulators

Heat Insulators are the opposite to conductors.

Heat Insulators are substances that are poor conductors of heat.

These include: Plastic, Gases, Blankets

Page 9: Yr9 - conduction and insulators

Heat Insulators Insulators keep you warm such

as blankets or keep substances cold such as an esky.

Insulators do not allow the transfer of heat.

Page 10: Yr9 - conduction and insulators

Quiz Name 10 heat conductors found around the home

Name 10 heat insulators found around the home

What are some ways you can quickly test to see if something is a good conductor or not?