VOLTAGE DIVIDER LAW

VOLTAGE DIVIDER LAW

When resistance are connected in parallel with a voltage source, E, the potential difference across the two resistors will be equal and the same as the voltage supplied by the source E.

Figure 1

For example in figure 1 above, V_in = V_R1 =V_R2 = V_out

On the contrary, when the resistors R₁ and R₂ are connected in series with each other and with the voltage source as in figure 2 bellow;

Figure 2

In figure 2, V_R1 and V_R2 is the voltage across R₁ and R₂ respectively,

V_in = V_R1 +V_R2

Since the same current is passing through the resistance in series,

            V_R1 = IR₁

            V_R2 = IR₂

            Vin =  I×R_T (Ohms law)

            R_T = R₁ +R₂ (resultant resistance in series)

Now, we can say;

or

This is known as Voltage Divider Law.