Electricity
Generation
with
Magnets or Lemons
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If you want to do something
useful - you need energy

We feel tired when we run out of energy

So we eat to give us energy.
2
Our energy comes from food.



When we eat
we can walk, think, run, lift, turn, push, pull,
and ------
We need energy to work and play.
3
Energy makes things work
4
What do we need to make
these work?
Electricity!
5
Without electricity - We might use
 Candles
 Coal fires
 Semaphore to send
messages
 Piano
- - Without electricity our lives would be very different.
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What is electricity?
 It is the movement of very, very tiny
particles called electrons.
 As the tiny, tiny particles move they carry
energy
 Electricity flows through wires
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Supply of electricity
Electrons
Switch
Light bulb
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How big are electrons?

How many electrons in a piece of
copper wire 1mm thick and 10cm long?
100,000,000,000,000,000,000
One hundred million million million
or one hundred billion billion
Electrons are very, very small
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Electricity transports energy from
one place to another
For this we need:
• A complete circuit made of conductors
with lots of electrons
• Something to provide energy to push
the electrons round the circuit
• To where we want to use it.
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Why is electricity important?



It can make things work.
It is easy to move the energy
around using wires
to just where you want it!
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How is electricity made?
We need something to provide energy to
push the electrons around the circuit.
2 main choices:
A battery
or
A generator
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Lemon battery
13
A battery
- uses chemistry to release energy
 Portable
 Cheap
 only store a fixed amount of energy
 big, heavy batteries are needed to store lots of energy
In a car
a large battery is used
to start the engine
and light the lamps.
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Generators



Use energy to make electricity
A moving magnet is able to push the
electrons along a wire.
The energy to move the magnet is
carried by the electricity,
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Magnet
Electrons
Light bulb
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Magnet
Magnet has to move to make electricity
Electrons
Light bulb
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We can generate electricity
coil
switch
lamp bulb
magnet
- by moving a powerful
magnet through a coil
of wire.
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What have we learned?



Energy makes things work.
Electricity can carry energy to
where we need it.
Electricity can be made using
a battery
2. a generator.
1.
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

We can
generate
electricity but only small
amounts
- even when
we work hard.
Huge generators as big as
houses are needed to generate
electricity for homes, factories
and schools.
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