How power is distributed in a house; extending a circuit
Caution: Before working on an electric circuit, shut off power to it at the fuse box or circuit breaker panel.
Electricity flows along a continuous wire circuit from a power plant to a power-drawing device such as a lamp or appliance and back again. The amount of current flowing past a given point in a wire is measured in amperes or amps. The pressure that forces current through a wire is measured in colts. The use of electricity is measured in watts, which are equal to volts multiplied by amperes.