An analogy used to explain science:
"Tesla coils are high frequency, high voltage, they're a little bit different to lightning which is high current, high voltage. If you use the waterfall analogy, voltage is the height of the waterfall, and the current is the amount of water coming over it, because you can imagine that a waterfall which just has little drips coming off it, if you are standing at the bottom that's not going to feel like much."
Dr Daniel Mitchard (Senior Lecturer, Cardiff School of Engineering, Cardiff University) was talking on an episode ('The Shock Factor') of the BBC Radio 4 programme/podcast 'Curious Cases'.
This seems a productive analogy, as long as it is recognised it inherently includes resistance – drops of water soon reach a terminal velocity because of air resistance – otherwise drops from a very tall waterfall could do a lot of damage as they would be moving very fast at impact. Similarly in a simple circuit, closing a switch leads to the p.d. acting accelerating electrons, but the resistance very quickly leads to a constant drift velocity.
Read examples of scientific analogies
