Heating and Cooling

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Heating and Cooling
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Heat and Temperature
Heat is a type of energy that will flow from a
warm area to a colder one. For example
This cup of coffee will ____ ____ because it is
_____ ____ heat energy into the surroundings.
This drink (taken out of the fridge) will _____
___ because it is _____ ___ heat energy from the
surroundings.
Words giving out, warm up, taking in, cool down
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Heat energy
How much heat energy an object has depends on its
temperature AND how much of it there is
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Particle theory revision
Particle theory is all about explaining the
properties of solids, liquids and gases by
looking at what the particles do.
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SOLIDS
In a solid the particles ______ around a _____
position. There is a ______ force of attraction
between each particle and they are very _____
together
Words strong, close, vibrate, fixed
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Heating a solid
When a solid is heated it expands. We can use
particle theory to explain why
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When a solid, liquid or gas heats up it will
expand. When a solid, liquid or gas cools down
it will contract.
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Changes of state
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Changes of State
What are these processes called? Choose from
freezing, evaporating, melting, condensing
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Heating ice
Temp/OC
Time/s
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Conduction
CONDUCTION is when heat moves through a ________.
Metals are better conductors of heat than
plastic or wood. This is why
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Conduction
In this experiment we saw that liquid water is a
poor conductor of heat. The ice cube did not
melt even though the water above it was boiling.
Air is also a poor conductor of heat. This is
how many types of house insulation and clothing
keep us warm.
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Radiation
When you wear a black t-shirt on a hot, sunny day
you would feel ______ than if you wore white.
This is because black ________ infrared radiation
(i.e. heat) from the sun better than white does.
Im cool!
Im very hot!
Conduction is when heat travels through a solid
and convection happens in a liquid or gas, but
radiation can happen through absolutely ________
because the heat is moving by ______. This is
how heat reaches us from the ____.
Words sun, absorbs, nothing, warmer, waves
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Convection
Convection is all about when a gas or liquid
(fluid) moves and carries heat with it. When
the fluid is heated it ____________. This means
that it will become less __________ than the
colder fluid around it. Because of this the
warmer fluid will try to _______ over the
colder fluid, and this is why warm air rises.
This is called a convection ___________. This is
how heat reaches us from the ___________ in this
room.
Words to use expands, radiators, dense, heated,
current, float
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Evaporation
Heat can also be lost when water evaporates (this
is how we cool off when we sweat)
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