There are two key ideas that you need to grasp when trying to understand electric circuits.
There's something that moves and there's something that batteries run out of, and they're different.
The things that move are charges. They are already there everywhere in the circuit and they all start moving very slowly everywhere at the same time as soon as the circuit is connected. Charges aren’t lost, they just go round and round.
The stuff that batteries run out of is energy. Energy is transferred from the battery to the components in the circuit almost instantly. Though the mechanism for this transfer is very complex, it can help to imagine that each charge carries with it some energy, which it transports from the battery to the components.
This model of individual charges carrying energy, though not strictly correct, makes it easier to understand qualitatively the ideas of current, voltage and power.
Our interactive circuit animation models charges as black blobs and energy as a red glow.
Hi Julian. Am currently helping my daughter with her GCSE physics and came across Furry Elephant. Would just like to say that I wish I had had access to this when I did my A-level physics cos then I might have actually passed! It is brilliant! I see that you have also started doing PSHE subjects which look great. Is there anything else in the pipeline? Prozac Newton
ReplyDeleteHi Prozac. Thanks so much for the kind words. There's a lot of work (and love) that went into Furry Elephant and I'm really glad to hear it spoken of so well. I'll be working on some Forces and Motion resources in the future but it's not going to happen overnight, I'm afraid. Best wishes.
ReplyDeleteHi Julian
ReplyDeleteI was wondering if you could suggest/know of a book that explains electricity with the same/or a similarly accurate analogy as the one you use on the furry elephant.
Regards, Christian.