Resistors in Series

RESISTORS IN SERIES

When resistors are connected as in figure 1.9 such that the same current passes through all of them, they are said to be in series.

Each resistor has a voltage drop across it given by Ohm's law. Thus,

V₁ = IR₁; V₂ = IR₂ and V₃ = IR₃ ……. (10)

The total drop in the three resistors put together is

V = V₁ + V₂ + V₃ = IR₁ + IR₃ …… (11)

Thus the circuit behaves as if a single resistor, R equal to R₁ + R₂ + R₃ is connected across the battery of V volts.

Figure 1.10 shows the equivalent of figure 1.9. Hence, the total effective resistance of a number of resistors connected in series given by

In the circuit of figure 1.10 the power dissipated in R1 is given as

In a series circuit,

1. The same current flows through all the resistors.sups sidudative

2. For each resistance, there will be a voltage drop according to Ohm's law.

3. The sum of the voltage drop will be equal to the applied voltage.