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I know that in AC, the direction of the flow of electrons is constantly changing, but this question is for a DC circuit like an LED with a battery.

Does current in such a circuit flow from the - side of a battery to the + side of a battery? This makes sense to me as the negative side wants to get rid of the negative electrons as it has too many, and the positive side wants to gain electrons so they move in that direction.

But recently I've heard that it's actually the other way round? + > - I've also heard this is to do with how electricity was first discovered and they got it wrong? Now I'm really confused on which way it actually flows, or if it's just the naming of the positive and negative sides of a battery are inverted..

Could somebody shed some light on this? I would appreciate it very much.

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    $\begingroup$ There is a convention for the technical direction of the current: positive current flows from the plus pole of a battery to the minus pole by convention. The microscopic details of conduction in a specific medium/conductor are a different thing. In some conductors, like metals, it is actually electrons that flow. In other media, such as ionic solutions, there can be both positive and negative ions that contribute to the current. $\endgroup$ – flaudemus Feb 19 at 17:46
  • $\begingroup$ Beginners can be misled by the idea that electrons "flow". In a simple circuit made from say a battery, a lamp, and a switch, each individual electron would take of the order of one hour to make a complete loop around the circuit. The idea that when you flick a light switch in your house, electrons somehow travel instantly down the wires from the power station to your house, is completely wrong. $\endgroup$ – alephzero Feb 19 at 18:38
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The direction of current actually is a convention. Before we knew that electrons were the moving charges, people thought that the positive charges were the ones responsible for the current. But it doesn't matter, there are 2 sign flips when you change from negative to positive or visa-versa: one for the direction of current, and another for the sign of the charge. You end up with the same answer as before.

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Current flows from the + side to the - side. However, electrons flow from the - side to the + side. These statements aren't contradictory when you understand what current is.

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  • $\begingroup$ Would you mind expanding a bit? As I understand, current is the flow of charge, which is electrons. So the direction of flow of charge and electrons are the same? Is this incorrect? $\endgroup$ – marc morgan Feb 19 at 18:51
  • $\begingroup$ You are incorrect. Current is the flow of positive charge which is physically equivalent to the flow of negative charge in the opposite direction. $\endgroup$ – PiKindOfGuy Feb 19 at 18:56
  • $\begingroup$ Electrons going from the - side to the + side is equivalent to positive charges moving from the + side to the - side. Thus current moves from the + side to the - side. $\endgroup$ – PiKindOfGuy Feb 19 at 18:58

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