An electric circuit is formed when the electrons from a voltage or current source flow, but most circuits have more than one device that receives electric energy. Most of the devices in a circuit like a light bulb, resistor, or a capacitor are connected in one of two ways, series or parallel. When it’s connected in series, the devices form a single pathway for electron flow between the terminals. Then when it’s connected in parallel the wires form branches; this means that it separates the path for the flow of electrons. Parallel and series both have their own different way to connect and they are calculated using different formulas.

Series is an electric circuit in which electrical devices are connected along a single wire so that the same electric current flows through all of them. What this means for resistance is that it’s greater, because the electrons all go through the same path through the circuit. The way to find series is to find the total resistance by using the formula: Rt= R1+ R2+ R3. This means by using the different amount of resistance in the circuit then adding them together, so that the total resistance is calculated. Then since the electrons go through in one path then the current goes slower. In contrast to a series circuit, the electrons in a parallel circuit don’t go through just one loop in one pathway. The electrons go through different loops so this means the resistance isn’t greater compared to series; the current is greater because they have more pathways to go through. Parallel circuit is an electric circuit in which electrical devices are connected in such a way that the same voltage acts across each branch, and any single one completes the circuit independently of all the others. We can calculate the total resistance in a parallel circuit by using the formula: 1 over Rt = 1 over R1+ 1 over R2 + 1 over R3. By using the formula the total resistance is found, but an important thing to keep in mind is to reverse the answer.

Then there are different examples of series and parallel circuits. For example in earlier automobiles both headlights went out when one bulb burned out. The headlights must have been connected in series because if one of the headlights burned it would cut the electric flow to the other bulb as well, making them both out of operation. Examples of parallel circuits are used all over homes like multi-bulb lights and Christmas lights. The parallel circuits make sure that if one of the bulbs burn out then the others will still light up.