Year 7 Electrical Circuits

If you’re living in Australia in the 2000’s there is a near impossible chance that you have avoided electricity or it’s impacts in your lifetime. We use electricity to power almost anything and everything that can be moved, sounded or illuminated. This lesson covers how we allow electricity to flow through these systems.

What is Electricity?!?!

Electricity can be broken down into 3 related variables with the following equation ” V=IR ” ( Voltage = Current x Resistance)

  • Voltage (V)
  • Current (I)
  • Resistance (R)

As we work within this lesson we won’t discuss the variables very much, but we will learn more about what they mean by exploring electricity.

Sooo, what is electricity then?

Well to explain it simply, all atoms have protons, neutrons and electrons. Most atoms really like their electrons and want to hold onto them.
Metals are rather large and don’t notice their outer electrons as much. e.g. copper is a great conductor of metal (below).
When you turn a generator you can send a “flow” of electrons through a wire and they will keep bumping into each other down the wire until they’re at the bottom of the flow, or “grounded”.
While the electrons are “flowing” we can make them do work, e.g. compress air for a fridge, heat a room, turn a fan, power a projector and computer etc.

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Atom of copper with all it’s electrons

How to draw a simple electric circuit

Below are the simple components that we will use to draw electric circuits. Make sure to copy them into your book for quick and easy reference in the future.

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Note: Batteries are made up of more than 1 cell which is why they are drawn here with “- – – -” in-between.
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Note: longer line is positive, shorter is negative. Electricity always flows from positive to negative

Playing with electrical circuits

There are 2 ways which we can play with electricity, virtually or practically.

Year 7 Energy Topic
Year 7 Energy Topic Vocabulary