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8/3/2019 Energy - Conduction
http://slidepdf.com/reader/full/energy-conduction 1/11
Starter: Types of Energy 2
This is the energy possessed by
ELECTRICAL CURRENT.
The is the energy an object has if it is high up.
This is the energy stored in
FUELS, FOOD and BATTERIES.
It is released through CHEMICAL
REACTIONS.
Electrical Energy
Chemical Energy
Gravitational Energy
8/3/2019 Energy - Conduction
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Lesson 3 Objectives
To learn about conduction
8/3/2019 Energy - Conduction
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Lesson 3 Outcomes
To know when conduction
occurs
To know what a conductor is To know what an insulator is
8/3/2019 Energy - Conduction
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Why «
Do we cook with wooden spoons?
Why don¶t we use metal spoons?
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Thermal Insulators
INSULATORS are MATERIALS that will NOT LET HEATPASS THROUGH THEM EASILY. Which materials below do
you think are good insulators of heat?
Glass
Paper
Air
Rubber
Wool
Steel
Brass
Tin
What do you notice about all the insulators?
They are all NON-METALS.
Non-metals are
good insulators
8/3/2019 Energy - Conduction
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Thermal Conductors
CONDUCTORS are MATERIALS that will LET HEAT PASSTHROUGH THEM EASILY. Which materials below do you
think are good conductors of heat?
Plastic
Copper
Rubber
Glass
Aluminium
Wood
Iron
Gold
What do you notice about all the conductors?
They are all METALS.
M etals are good
conductors
8/3/2019 Energy - Conduction
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Heat Transfer
Heat needs to travel through different
substance. To do this, it needs to travel
in different ways:1. Conduction
2. Convection
3. Radiation
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ConductionCONDUCTION is when heat moves through a solid. Metals arebetter conductors of heat than plastic or wood. This is why«
These parts aremade of plastic
or wood:
These parts aremade of metal:
Heat energy is passed on to neighbouring particles by
VIBRATIONS, best in SOLIDS
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Investigating Conduction
1. Hold a WOODEN ROD and a
COPPER ROD in your hands. Place
the ends of the rods in the YELLOW
SAFETY FLAME of a Bunsen. What
happens? Why?
2. Hold an IRON ROD and a COPPER
ROD in your hands. Place the ends
of the rods in the YELLOW SAFETY
FLAME of a Bunsen. What happens?
Why?3. Look at the rods ± steel, copper,
glass and wood with drawing pins
stuck on with wax. On which rod will
the pins fall off first and why?
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Exercise 1: Conduction Results
1. Which rod became warmer fastest, wood or copper?
2. What does this tell you?
3. Which rod became warmer fastest, iron or copper?
4. What does this tell you?
5. Why did the ice not melt quickly?
Copper rod became warmer faster
Copper is a better conductor of heat than wood, metals are better
conductors than non-metals
Copper
Different metals conduct heat at different rates
Water (liquids) are poor conductors of heat