on video Electrical Current Explained - AC DC, fuses, circuit breakers, multimeter, GFCI, ampere



Current is the flow of electrons in a circuit. To use electricity, we need electrons to flow in the same direction around a circuit, we usually use copper cables to form the circuit because copper is a very good electrical conductor, which means the atoms that make copper have a loosely bound electron in that outermost or valence shell, which is free to move around inside the metal.

This free electron is very easy to move, which is why copper is so popular. It's so easy to move that it will naturally move to other copper atoms by itself. But this happens randomly in any and all directions, which is of no use to us. We wrap copper wires in rubber because the rubber is an insulator, which means it does not allow free electrons to pass through it. That provides a barrier and keeps the electricity within the wires and away from us.

  For us to use electricity to power our devices- we need lots of electrons to flow in the same direction along a circuit. We can then place things like lamps in the way of these electrons so that they have to flow through it and generate light and heat in the process. To do this, we need to force the electrons to move and we can do that by applying a voltage. Voltage is the pushing force, it's like pressure in a water pipe. The more pressure we have, the more water can flow, the more voltage we have, the more electrons can flow.

We can measure pressure without there being any water flowing, and we can measure voltage without there being any current flowing. But we can't measure how much water flows if no water flows. And we can't measure the electrical current if no electrons are flowing, if we take a copper wire. There is no voltage difference between the two ends so the free electrons move around randomly. This random movement is not considered a current one. But if we take a battery of, say, one point five volts and connect the wire across the two terminals, then there is now a difference of one point five volts across the wire

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