How does electricity know which is the path of least resistance?


How does electricity know which is the path of least resistance?

In: Physics

Because it just is. Think about it, if you cut two holes in a tire, then put scotch tape over one and gorilla glue in the other… what would happen when you went to fill it with air? How does the air know which hole has the least resistance?

For the same reason a ball will roll in the steepest direction. It’s kinda just…how the universe works. The direction that allows for the quickest decrease in potential energy is the direction that something will travel if given the opportunity. In general, the lower the potential energy, the “more stable” that state is, and the universe is quite interested in the most stable, least energetic state in basically every circumstance.

Nothing in nature knows anything except us and possibly some animals. Everything in nature follows certain laws and this manifests as a pattern which may allows us to say things like current will take the path of least resistance. There’s nothing special here same thing applies for water flowing in a pipe, if there’s less resistance, it flows more through that path than the rest because it can.


When you fill a balloon with water, the balloon stretches to accommodate it. But, the water and the balloon are always trying to to reach a state of equalibrium.

For the balloon, it’s state of equalibrium is what it looked like before you fill it up with water. For the water, it doesn’t want to be pushed on by the balloon that is trying to reach equalibrium.

If you did not tie the balloon, both the water and balloon would return to their equalibrium states; the water would leave the balloon and the balloon would shrink back to normal.

For electrons, this also applies. Imagine the balloon as a battery on a circuit and the water as the electrons.

When you fill the circuit with electrons, they will flow to where they can reach equalibrium. When you close the balloon, it’s like flipping a switch OFF and disconnecting the battery from the circuit on one end. The electrons will stay there, but as soon as you open the balloon (flip the switch to ON) those electrons will flow to wherever they can so they can reach equalibrium.

It doesn’t.
Electricity will flow down all paths. However, low resistance means it has an easier time flowing (by definition) so that’s where most of the electricity ends up.