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Parallel or Series

Parallel Circuit

Some components are connected parallel with each other. When some of the components are connected parallel with each other they form a parallel circuit. A voltmeter must be wired in parallel in a circuit in order to measure the difference in EMF.

Series Circuit

Closed Circuit where a current follows one path. When all the components are in line with each other and the wires, a series circuit is formed. A load is any device in a circuit that is using the energy that the electron current is delivering to it.


Electromotive force or potential difference expressed in volts. EMF causes the electrons to move in a particular direction. EMF is measured in units called volts.


Term which describes the forces that oppose the flow of electron current in a conductor. Resistance is measured in units called ohms. Resistance is sometimes desirable and sometimes undesirable.


Components useful to cause explosions and a fire to not happen.