Friday, October 14, 2011

Homework: potential difference analogy

By the way, Dre, thank for creating the blog and sharing the video with us.

An analogy I use most is to explain the difference between current and voltage. It is the Christmas Father analogy. Christmas father (Mr Coulomb) leaves the battery with his sack full of presents (energy). His pace represents the current. When he passes the bulb his sack is empty so now there is a potential drop. He still continues moving, to go fill the sack again, so the current is the same.

I couldn't upload the image I use but this is a very similar idea. I use Christmas father instead of the containers.

See all soon.


  1. Good analogy. One question though... how do you explain that the bulb does not light if there is a gap in the circuit after the bulb (ie between bulb and -ve terminal)?

  2. As there is a gap, the Christmas Father close to the gap can't move. So no movement is possible and no one can leave the battery. Like the que of cars in a traffic jam.