Now that we have discussed the basics of electrical circuits, let's build our first circuit. In this circuit, we will simply light up a LED. We will start off with a look at the schematic diagram, which will tell us how to build the circuit:
In this diagram, we can see that the circuit consists of one 9-volt power source (9-volt battery) one LED and one resistor. One of the first questions people new to circuits ask is how we calculate the value of the resistor. To calculate this value, we need to know what the forward voltage for the LED is and the maximum current it can take without blowing. The forward voltage is the voltage amount required before the LED will conduct electricity and the voltage drop that will occur. If you purchase the LED from a good electronic store, they should have a datasheet that will tell you the forward voltage and the maximum current...