• Learn the expression for the equivalent resistance of a series connection of resistors in terms of their individual resistances.
• Learn the expression for the equivalent resistance of a parallel connection of resistors in terms of their individual resistances.
• Learn the expression for the equivalent conductance of a parallel connection of resistors in terms of their individual conductances.
• Learn the expression for the equivalent resistance of two resistors connected in parallel.
• Learn the expression for a voltage divider and the condition on load resistance under which it applies.
• Learn the expression for a current divider.
• Learn the way in which a Delta (or Pi) configuration of resistors can be transformed into a Y or T configuration and vice versa.

Skills: In studying the material in this chapter, you should make certain that you develop the following skills:

• Find the equivalent resistance of series or parallel combinations of individual resistors.
• Find the equivalent resistance of a ladder network consisting of alternating series and shunt resistors.
• Apply the voltage divider analysis method to a circuit in which the load resistor is much greater in value than the values of the voltage divider resistor.
• Find the values of shunt and series resistors which can be used to change the scales of a D'Arsonval ammeter or voltmeter.
• Use a Wheatstone bridge to find the value of an unknown resistor.

Review Questions: Test your understanding of the material in this chapter by answering the following review questions:

1. If the load resistor connected across the output of a voltage divider is not considerably larger than the voltage divider resistors, how can the voltage divider method be modified to give the correct result?

2. If the voltages applied to the three terminals of a Delta configuration of resistors are the same as the voltages applied to the three terminals of an equivalent Y configuration, is the total power dissipated in the circuit the same?

3. Find a simplified form for the Delta-to-Y and Y-to-Delta expressions that applies to the case where the resistors in either of the configurations have the same value.