Note: for a more in-depth look at circuits, see here!

So, you know all you need to know about circuits, but you’re a bit stuck for how to explain it? Take a look at this simple definitions to help you along:

  • Potential Difference: The amount of energy transferred per coulomb of charge.
  • Current: The flow of electrons in a circuit (they flow from negative terminals to positive terminals!)
  • Resistance: This happens when an electron collides with an atom, and causes heat.

And here’s some helpful things to remember:

Series Circuits:

  • Current stays the same in a series circuit (as the electrons can only go one way)
  • Potential Difference is shared in a series circuit. (Thanks to different resistances)

Parallel Circuits:

  • Current is shared in a parallel circuit (like a fork in the river). The electrons are able to go two or more ways.
  • Potential Difference is the same in a parallel circuit (as the potential difference will always add up again at the ‘end’ of the circuit.

So really, they’re just opposites!


UK Plug Wiring

So, this is it people. After this post, you’ll be able to read and understand the whole AQA P2 Physics specification without ever leaving Revision Systems! It’s taken a lot of words for us to get to this point, but hopefully you’ll find it useful. So, here we go. On this final stretch we’ll be looking at:

  • Plugs (and their wiring, as seen above)
  • Power
  • The dangers of electricity (although these are fairly obvious, so we won’t go into too much detail.)

So, let’s go!

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A/C Oscilloscope Trace

Above this paragraph is a bog-standard oscilloscope trace, from an alternating current (AC) power source. Unfortunately, in the exam, you might be asked to do a bit more than simply look at an oscilloscope trace. That’s why in this article, we’re going to cover what an oscilloscope trace is, what AC and DC are, and the differences between the two.

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Fuse Circuit Symbol

So, what is a fuse? What’s a circuit breaker? How does a fuse work? What’s the difference?! All of these are very relevant questions, and thankfully, all of them are relatively simple to answer, too. For the P2 exam, you need to know what a circuit breaker is, what a fuse is, how they work, when we use them, why we use them, and some advantages and disadvantages. So… Do you have some popcorn? Are you comfortable? If the answer to any of the previous two questions was ‘no’, then you might want to fix that and come back straight away!

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Electrical circuits are another section of many physics exams, and so we’re going to do a little bit of revision about them, this should be a fairly quick and easy read, but let us know all the same if you have any problems with it…

Everybody’s been doing basic electric circuits since primary school, making a light bulb light up, being annoying by constantly powering a buzzer, but some of the more complicated components don’t get introduced until later, and guess what: you need to know what they look like on a diagram!

Click through to begin learning about all things circuit diagrams…

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