Module 2: Series Circuits Module Objectives: Upon completion of this module, students should be able to: 1. Explore the idea of a series circuit. 2. Understand how to draw a circuit diagram of a series circuit.
Upon completion of this module, students should be able to:
1. Explore the idea of a series circuit.
2. Understand how to draw a circuit diagram of a series circuit.
3. State the voltage, current, resistance, and power characteristics of a series circuit.
4. Solve for unknown circuit values in a series circuit.
5. Use a multimeter to measure the potential differences (voltages),
currents and resistance of series circuits.
6. Apply the concepts of relative polarity, series adding, and series
7. Study the applications of voltage divider calculations
8. Apply Ohm’s Law to calculate resistance, voltage and current in
9. Verify Kirchhoff’s Voltage Law in a series circuit.
10.Recognize some basic applications of series circuits.
2.1 Introduction to series circuits
A series circuit is a circuit that has only one path for current flow.
Circuit diagram shows the physical details of the circuit.
Schematic diagram uses symbols to represent each circuit component.
• If a lamp 'blows' or a component is
disconnected, all the components
• If you put more lamps into a series
circuit, the lamps will be dimmer.
2.2 Identifying Circuit Components
Current is the samein the series circuit
In a series circuit, the total voltage equals the sum of the voltage across the batteries wired
in series in the circuit.
In a series circuit, the total resistance (in ohms) equals the sumof the resistance of each device using electricity.
IT = I1 = I2 = I3
VT = V1 + V2 + V3
RT = R1 + R2 + R3
The total power dissipated (Pt) in a series
circuit is always the sum of the power
dissipated by the individual resistors or
the product of the total current (It) and
the source voltage (Vt).
Two lamps are
PT = IT x VT
Ohm's Law can be used to solve for any
of the individual values or for the total
value of each measure within the series
When the polarities of the power sources
are connected in the same direction as
shown here, they are referred to as Series aiding
When the polarities of power sources are
connected in opposite directions as shown, their voltages cancel, and are referred to as Series opposing
Solve example 1.1 - page 10
The two resistor voltage divider as shown here is used often to supply a voltage different from that of an available battery or power supply.
The voltage drop across any given
resistor in a series circuit is equal to
Solve example 2.2- page 11
Kirchhoff’s voltage law (KVL) is generally
Thesumof all the voltage drops around a single closed path in a circuit is equal to
the total source voltage in that closed path.
Solve exercises - page 17,18