7.2 AC V OLTAGE A PPLIED TO A R ESISTOR

. AC V OLTAGE A PPLIED TO A R ESISTOR Figure . shows a resistor connected to a source ε of ac voltage. The symbol for an ac source in a circuit diagram is ~ . We consider a source which produces sinusoidally varying potential difference across its terminals. Let this potential difference, also called ac voltage, be given by sin v v ( . ) where v m is the amplitude of the oscillating potential difference and ω is its angular frequency. To find the value of current through the resistor, we apply Kirchhoff’s loop rule ( )