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All substances are made of atoms.
Atoms contain particles called electrons that revolve around a central nucleus.
In a conducting wire each atom has one or more free electrons.
Each electron has a negative charge, which is balanced by the positive charges within each nucleus. The free electrons move randomly when
no battery is connected. However, when a battery is connected the electrons move towards the positive
end of the battery, creating a flow of electric current.
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All materials are made from millions and millions of tiny particles called atoms.Each atom contains negatively charged electrons that orbit a positively charged
central nucleus. The nucleus consists of smaller particles called protons and neutrons. | |  | | In a conducting wire the free electrons jump between atoms at random. When
a battery is connected, the electrons jump between atoms but with an overall
movement towards the positive end of the battery. | |  |
A chemical reaction inside the battery increases the number of electrons at one end (the negative terminal) and a reduces the number
of electrons at the other end (the positive terminal). The electrons repel each other at the negative terminal and so they are
'pushed' into and through the conducting wires. The positive terminal attracts the electrons, pulling them through the conducting
wires. |
Now you have completed Lesson 5
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