Series and Parallel Networks
Figure 3.1 shows three resistors R1, R2 and R3 connected end to end, i.e., in series, with a battery source of V volts. Since the circuit is closed, a current I will flow and the voltage across each resistor may be determined from the voltmeter readings V1, V2 and V3.
Figure 3.1 : Series circuit
In a series circuit:
(a) the current I is the same in all parts of the circuit; therefore, the same reading is found on each of the two ammeters shown, and,
(b) the sum of the voltages V1, V2 and V3 is equal to the total applied voltage, V, i.e.,
From Ohm’s law:
V1 =IR1, V2 =IR2