Electricity doesn’t travel through wires

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I saw a few youtube videos explaining that electricity doesn’t actually travel through wires but directly to the bulb from the battery. I understood their explanation. But now I have a doubt. Since energy flows directly to the bulb, can I shield the bulb in some way such that the circuit is complete and even then the bulb doesn’t light up?

In: Physics

13 Answers

Anonymous 0 Comments

Electricity does travel through wires, just not in the way you were thinking.

This is a good response to the video you may be talking about.

This whole thing comes under a well studied topic called transmission lines, because this is very important in the way you deliver power to homes that are far from a generating station.

The commonly taught models which show electricity instantly travel, which may be where this misconception comes from, does not consider wires that are very very very long. When wires become longer you have to consider things you didn’t when the wires were small. Like the effect created by the flow of energy that tries to oppose the flow of energy, or the interaction of the wires kept parallel to each other, and even the fact that wire inherently doesn’t want to conduct energy.

When you model those very long lines you see that electricity flows as waves, rather than instantaneous power. So in your question, there can be points in time where even if the switch is closed, enough power isn’t reaching the bulb instantaneously. But after a while it could reach a peak enough to turn it on.

But your question seems to be a little conflicting. If you are trying to shield your wire in some way, you are preventing the flow of energy in some way. If you are preventing energy flow in some way, the simplest way is to have no connection. The tougher, longer process would be to make wires unconductive in some way, so that energy doesn’t flow through them easily. But then at that point, why even try to turn on the light?

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