Internet Guide to Electronics

Conductors

Circuits, what is up with that? First you need to understand how all the parts of a circuit relate. The main thing that a circuit has is conductance and that all the parts are conductors. Conductors are materials in which electric charges move freely. If the material isn't a conductor, it is either a insulator or a semiconductor. Conductors are mainly metalic substances such as copper, aluminum, and gold. Conductors allow a charge to build up and move "freely" through the conductor. When dealing with circuits and the moving of electrons, free movement at the moment is the best movement. I will get to reasons to but a damper on the movement of electrons later. Now, if a conductor allows a charge to build up and move freely, then it should be easy to understand that an insulator is just the opposite, it might build up a charge but that charge isn't going anywhere. Semiconductors is the crossbreed of the other two types. Semiconductors are usually a conducting material that has been "doped" or has been added to from a insulating material. This makes it so the charges don't want to move as freely but they can still move.

Now, just like lightning, charges have a tendency to try to make their way to the earth if they can. This is why if you have a conducting material and connect it to the earth with a wire or something, it is said to be grounded. Grounding is a good thing to do with circuits because if there is too much charge going through a circuit, you don't want it to stay in the circuit and fry everything, grounding a circuit is generally safe. To finish off the idea of the very basic circuit, we know that it allows a charge to build up and move through it, now we need to know that the circuit must be complete. The ending picture of the circuit must make a complete loop so that those charges that like to move have somewhere to allways go. What happens if you hook a wire from one end of a battery to nothing else.....NOTHING. The circuit is not completed therefore the charges can't move off the end of the wire and continue to go.

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So now we are ready to move on. You now have a basic understanding of why wires are made of metal and not wool. We have an idea of a circuit as being a completed loop of conducting materials that let charges go round. You can either go back to the list of pages HERE, or move on to the basics of voltage, current, and resistance HERE.