Question

4. Use voltage divider concepts to find the voltages indicated in the following circuits. You may want to use some of your results from problem 1. You may need to use the voltage divider equation more than once.

Answer 1

Hello, because there is not a circuit I'll explain the voltage divider and make an exercise, this way you can solve the problem using the method described here.

Answer with explanation:

A voltage divider uses the voltage distribution among components to find a voltage in a specific element of the circuit. If we have a source V1 connected to impedances Z1 and Z2 in series, we can use a voltage divider to find the voltage across Z1 or Z2 base on their value and the input voltage.

VZ1 = V1*Z1/(Z1+Z2)

VZ2 = V1*Z2/(Z1+Z2)

In the image, to find the voltage Vo across R2 we apply the following equation: Vo = (V1*R2)/(R1+R2).

To solve the exercise in the other image, we need to apply a voltage divider twice:

In-circuit 1 we are asked to find the voltage VAB that falls on R2 and R3 (the same voltage for both resistances because are in parallel), to do so we use a voltage divider using V1, R1 and RT where RT is the equivalent resistance RT = R2//R3 + R4, therefore, for circuit two VAC = (V1*R1)/(R1+RT). After finding VAC we apply voltage divider again to find VAB, see circuit 3, to do so we apply VAB = (VAC*R2//R3)/(R2//R3 + R4) = (VAC*R2//R3)/(RT)