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Transcript
Lesson Plan
Course Title: Computer Maintenance
Session Title: Basic Electricity/Electronics
Lesson Duration: Five 45-minute class periods (time approximate)
Performance Objective:
Upon completion of this assignment, students will be able to identify, demonstrate, and discuss
the basics of electricity and electronics.
Specific Objectives:
• Define the basics of electricity.
• Assemble and explore the basic properties of a circuit.
• Demonstrate and discuss the basics of the digital multimeter.
• Demonstrate your ability to measure resistance and continuity with the multimeter.
• Demonstrate your ability to measure voltage safely with the multimeter.
• Describe the basics of signals and noise in communications systems.
Preparation
TEKS Correlations:
§130.273
1 (C) employ effective reading and writing skills;
1 (D) employ effective verbal and nonverbal communication skills;
1 (E) solve problems and think critically;
1 (F) demonstrate leadership skills and function effectively as a team member;
1 (G) identify and implement proper safety procedures;
3 (D) interpret appropriate documentation such as schematics, drawings, charts, diagrams,
technical manuals, and bulletins.
6 (A) use electronic test equipment to measure current, voltage, power, and resistance;
6 (B) describe digital circuits design;
Instructor/Trainer
References:
1. Cisco Systems Networking Academy Program: First-Year Companion Guide, Chapter 4:
Layer 1: Electronics and Signals.
Instructional Aids:
1. PowerPoint presentation: Basic Electricity/Electronics
2. Basic Electricity/Electronics exam
3. Labs 1 – 4
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
1
Materials Needed:
1. Copies of Lab Assignments (1 through 4). [For each student]
2. Various batteries (i.e. A cell, B cell, D cell, 9v and 6v lantern); for labs.
3. 1,000 Ohm and 10,000 Ohm resistors for each student or team; for labs.
4. Cat 5: jack, UTP cable, and patch cable for each student or team; for labs.
5. BNC terminated coaxial cable for each student or team; for labs.
6. Unconnected DB9 to RJ-45 adapter for each student or team; for labs.
7. Power supply (for laptop, or other networking electrical device); for labs.
8. Light switch for each student or team; for labs.
9. Copper wire; for labs.
10. 2 light bulbs (6v) with bulb bases for each student or team; for labs.
Equipment Needed:
1. Projection system to display the PowerPoint presentation (PC/Monitor, PC/Projector, etc.)
2. One digital multimeter for each student or team; for labs.
3. Wire cutter/stripper for each student or team; for labs.
Learner
1. Students should read the appropriate curriculum material for how computers work
(depending on the text/curriculum being used for this course). This lesson can be taught
with only the PowerPoint presentation and the equipment outlined above.
Introduction
MI
Introduction (LSI Quadrant I):
After it reaches a building, electricity is carried to workstations, servers, and network
devices via wires concealed in walls, floors, and ceilings. Data, which can consist of
such things as text, pictures, audio, or video, travel through the wires and are
represented by the presence of either electrical pulses on copper conducting wires
or light pulses in optical fibers. In this lesson you learn about the basic theory of
electricity, which provides a foundation for understanding how information is
processed by computers and communication systems.
Understanding electricity begins with understanding the basic unit of all matter –
the atom. Does anyone know what makes up an atom?
The atom is made of three tiny parts: protons, neutrons, and electrons. The protons
and neutrons are lumped together in a small grouping called a nucleus (the electrons
flow freely around the nucleus). When these three parts come together, they form
an atom.
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
2
Outline
MI
Outline (LSI Quadrant II):
Instructor Notes:
1. Introduce students to the parts of an atom.
2. Introduce students to the types of electrical
materials, including:
a. Insulators
b. Conductors
c. Semiconductors
3. Introduce students to measuring electricity,
including:
a. Voltage (V)
b. Current (I)
c. Resistance (R)
d. Alternating Current (AC)
e. Direct Current (DC)
f. Impedance (Z)
4. Introduce students to using a multimeter to make
measurements, including:
a. Resistance measurements
b. Voltage measurements
5. Introduce students to signals and noise in
communication systems.
6. Introduce students to analog and digital
signaling.
7. Introduce students to simplex, half-duplex, and
full-duplex transmissions.
8. Introduce students to baseband and broadband
concepts.
9. Discuss signaling and communication problems
with students.
10. Students complete lab demonstrations, including:
a. Lab 1: Using a Multimeter
b. Lab 2: Resistance Measurements
c. Lab 3: Voltage Measurements
d. Lab 4: Series Circuits
Application
MI
Guided Practice (LSI Quadrant III):
1. Teacher shows and demonstrates each lab principle.
2. Teacher maintains direct supervision in the lab, providing guidance when
warranted.
MI
Independent Practice (LSI Quadrant III):
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
3
1. Students work individually or in pairs on lab assignments, demonstrating their
skills in identifying and discussing the various lab requirements and results.
Summary
MI
Review (LSI Quadrants I and IV):
1. Ask students summary questions.
a. What are the two types of electrical current? Alternating Current (AC)
and Direct Current (DC)
b. What measurements can be made with a multimeter? Resistance
(Ohms), Voltage (AC and DC), and Continuity
c. What are the three required parts of an electrical circuit? Source or
battery, complete path, and load or resistance
Evaluation
MI
Informal Assessment (LSI Quadrant III):
1. Monitor student progress during independent practice and provide independent
re-teach/redirection as needed.
MI
Formal Assessment (LSI Quadrant III, IV):
1. Administer an objective multiple-choice test.
Extension
MI
Extension/Enrichment (LSI Quadrant IV):
Students that have mastered the lab assignments can peer-tutor students (one-onone) that are having difficulty using the multimeter.
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
4
Icon
MI
Verbal/
Linguistic
Logical/
Mathematical
Visual/Spatial
Musical/
Rhythmic
Bodily/
Kinesthetic
Intrapersonal
Interpersonal
Naturalist
Existentialist
Teaching Strategies
Personal Development
Strategies
Lecture, discussion, journal
writing, cooperative learning,
word origins
Reading, highlighting, outlining,
teaching others, reciting information
Problem-solving, number
games, critical thinking,
classifying and organizing,
Socratic questioning
Mind-mapping, reflective
time, graphic organizers,
color-coding systems,
drawings, designs, video,
DVD, charts, maps
Use music, compose songs
or raps, use musical
language or metaphors
Organizing material logically, explaining
things sequentially, finding patterns,
developing systems, outlining, charting,
graphing, analyzing information
Developing graphic organizers, mindmapping, charting, graphing, organizing
with color, mental imagery (drawing in
the mind’s eye)
Use manipulatives, hand
signals, pantomime, real life
situations, puzzles and board
games, activities, roleplaying, action problems
Reflective teaching,
interviews, reflective listening,
KWL charts
Cooperative learning, roleplaying, group brainstorming,
cross-cultural interactions
Natural objects as
manipulatives and as a
background for learning
Socratic questions, real-life
situations, global
problems/questions
Creating rhythms out of words, creating
rhythms with instruments, playing an
instrument, putting words to existing
songs
Moving while learning, pacing while
reciting, acting out scripts of material,
designing games, moving fingers under
words while reading
Reflecting on the personal meaning of
information, studying in quiet settings,
imagining experiments, visualizing
information, journaling
Studying in a group, discussing
information, using flash cards with
others, teaching others
Connecting with nature, forming study
groups with like-minded people
Considering the personal relationship to
the larger context
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
5
Computer Maintenance
Basic Electronics/Electricity Exam
Student Name: __________________________
Date: __________
DIRECTIONS: Circle the letter that corresponds to the best answer for each of the questions below.
1. Which of the following best describes an insulator?
A.
B.
C.
D.
Any highly malleable metal
Any material with a low resistance to electrical current
Any material that cannot transmit currents over 110 volts
Any material with a high resistance to electrical current
2. In electrical terms, what does AC mean?
A.
B.
C.
D.
Amplified current
Amplitude current
Attenuating current
Alternating current
3. Which of the following is the best definition of electrical current?
A.
B.
C.
D.
Force or pressure caused by the separation of electrons and protons
The measurement of electron flow in an electrical circuit
The opposition to electron flow in a circuit
The absence of electron flow in a circuit
4. What is the opposition to the movement of electrons as they move through materials?
A.
B.
C.
D.
Ohms
Voltage
Current
Resistance
5. Where is the safety ground connected on a computer?
A.
B.
C.
D.
Exposed metal parts
The monitor
The mouse
The network connection
6. Which of the following is the best definition of voltage?
A.
B.
C.
D.
Force or pressure caused by the separation of electrons and protons
The measurement of electron flow in an electrical circuit
The opposition to electron flow in a circuit
The absence of electron flow in a circuit
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
6
7. What is the unit of measure for resistance?
A.
B.
C.
D.
Volt
Ohm
Amp
Joule
8. When measuring voltage with a multimeter, which setting must be set?
A.
B.
C.
D.
Amperage range
Frequency
Polarity
AC or DC
9. What are the three required parts of an electrical circuit?
A.
B.
C.
D.
Switch, source or battery, load or resistance
Source or battery, complete path, switch
Source or battery, complete path, load or resistance
Power, source or battery, load or resistance
10. Which type of electrical circuit will have a continuously varying voltage-versus-time graph?
A.
B.
C.
D.
DC
Analog
Digital
Open
11. What is propagation of a network signal?
A.
B.
C.
D.
Travel
Delay
Latency
Attenuation
12. What is attenuation of a network signal?
A.
B.
C.
D.
Travel
Delay
A signal losing strength to its surroundings
A signal gaining strength from its surroundings
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
7
13. What is the result of impedance mismatch?
A.
B.
C.
D.
Brown outs
Power sags
Power surges
Reflected energy
14. Which of the following is an external source of electrical impulses that can attack the quality
of electrical signals on a cable?
A.
B.
C.
D.
EMI caused by electrical motors
EMI caused by fiber optic cable
EMI caused by DC batteries
Impedance caused by radio systems
15. What is the primary cause of cross talk?
A.
B.
C.
D.
Electrical motors and lighting
Too much noise in a cable’s data signal
Cable wires that are too large in diameter
Electrical noise from other wires in a cable
16. Which of the following best describes cancellation in cabling?
A.
B.
C.
D.
Wires in the same circuit cancel each other’s electrical current flow
Twisting of wire pairs provides self-shielding within the network media
The magnetic fields from separate cable cancel magnetic fields of another cable
External magnetic fields cancel the fields inside network cabling
17. Which of the following terms best describe the delay of a network signal?
A.
B.
C.
D.
Attenuation
Dispersion
Latency
Jitter
18. Which of the following terms best describe two devices communicating on a shared-medium
at the same time?
A.
B.
C.
D.
Obstruction
Dispersion
Collision
Latency
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
8
19. How many bits compose 1 byte?
A.
B.
C.
D.
2
4
8
16
20. Which of the following terms best describes the conversion of binary data into a form that
can travel on a physical communications link?
A.
B.
C.
D.
Encoding
Decoding
Encrypting
Decrypting
21. A channel is an allocated portion of the media’s available _______________?
A.
B.
C.
D.
Bandwidth
Transmission
Simplex Transmission
CPU processing capacity
22. What are the three parts of an atom?
A.
B.
C.
D.
Proton, nucleus, orbit
Electron, neutron, positron
Neutron, electron, proton
Proton, nucleus, positron
23. Which of the following would represent a DC source of electricity?
A.
B.
C.
D.
An electrical generator
A flashlight battery
A steam engine
A magnet
24. A multimeter can be used to measure which of the following?
A.
B.
C.
D.
Voltage, resistance, frequency
Voltage, resistance, continuity
Continuity, voltage, noise
Noise, frequency, voltage
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
9
Computer Maintenance
Basic Electronics/Electricity Exam
~KEY~
Student Name: __________________________
Date: __________
DIRECTIONS: Circle the letter that corresponds to the best answer for each of the questions below.
1. Which of the following best describes an insulator?
E.
F.
G.
H.
Any highly malleable metal
Any material with a low resistance to electrical current
Any material that cannot transmit currents over 110 volts
Any material with a high resistance to electrical current
2. In electrical terms, what does AC mean?
E.
F.
G.
H.
Amplified current
Amplitude current
Attenuating current
Alternating current
3. Which of the following is the best definition of electrical current?
E.
F.
G.
H.
Force or pressure caused by the separation of electrons and protons
The measurement of electron flow in an electrical circuit
The opposition to electron flow in a circuit
The absence of electron flow in a circuit
4. What is the opposition to the movement of electrons as they move through materials?
E.
F.
G.
H.
Ohms
Voltage
Current
Resistance
5. Where is the safety ground connected on a computer?
E.
F.
G.
H.
Exposed metal parts
The monitor
The mouse
The network connection
6. Which of the following is the best definition of voltage?
E.
F.
G.
H.
Force or pressure caused by the separation of electrons and protons
The measurement of electron flow in an electrical circuit
The opposition to electron flow in a circuit
The absence of electron flow in a circuit
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
10
7. What is the unit of measure for resistance?
E.
F.
G.
H.
Volt
Ohm
Amp
Joule
8. When measuring voltage with a multimeter, which setting must be set?
E.
F.
G.
H.
Amperage range
Frequency
Polarity
AC or DC
9. What are the three required parts of an electrical circuit?
E.
F.
G.
H.
Switch, source or battery, load or resistance
Source or battery, complete path, switch
Source or battery, complete path, load or resistance
Power, source or battery, load or resistance
10. Which type of electrical circuit will have a continuously varying voltage-versus-time graph?
E.
F.
G.
H.
DC
Analog
Digital
Open
11. What is propagation of a network signal?
E.
F.
G.
H.
Travel
Delay
Latency
Attenuation
12. What is attenuation of a network signal?
E.
F.
G.
H.
Travel
Delay
A signal losing strength to its surroundings
A signal gaining strength from its surroundings
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
11
13. What is the result of impedance mismatch?
E.
F.
G.
H.
Brown outs
Power sags
Power surges
Reflected energy
14. Which of the following is an external source of electrical impulses that can attack the quality
of electrical signals on a cable?
E.
F.
G.
H.
EMI caused by electrical motors
EMI caused by fiber optic cable
EMI caused by DC batteries
Impedance caused by radio systems
15. What is the primary cause of cross talk?
E.
F.
G.
H.
Electrical motors and lighting
Too much noise in a cable’s data signal
Cable wires that are too large in diameter
Electrical noise from other wires in a cable
16. Which of the following best describes cancellation in cabling?
E.
F.
G.
H.
Wires in the same circuit cancel each other’s electrical current flow
Twisting of wire pairs provides self-shielding within the network media
The magnetic fields from separate cable cancel magnetic fields of another cable
External magnetic fields cancel the fields inside network cabling
17. Which of the following terms best describe the delay of a network signal?
E.
F.
G.
H.
Attenuation
Dispersion
Latency
Jitter
18. Which of the following terms best describe two devices communicating on a shared-medium
at the same time?
E.
F.
G.
H.
Obstruction
Dispersion
Collision
Latency
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
12
19. How many bits compose 1 byte?
E.
F.
G.
H.
2
4
8
16
20. Which of the following terms best describes the conversion of binary data into a form that
can travel on a physical communications link?
E.
F.
G.
H.
Encoding
Decoding
Encrypting
Decrypting
21. A channel is an allocated portion of the media’s available _______________?
E.
F.
G.
H.
Bandwidth
Transmission
Simplex Transmission
CPU processing capacity
22. What are the three parts of an atom?
E.
F.
G.
H.
Proton, nucleus, orbit
Electron, neutron, positron
Neutron, electron, proton
Proton, nucleus, positron
23. Which of the following would represent a DC source of electricity?
E.
F.
G.
H.
An electrical generator
A flashlight battery
A steam engine
A magnet
24. A multimeter can be used to measure which of the following?
E.
F.
G.
H.
Voltage, resistance, frequency
Voltage, resistance, continuity
Continuity, voltage, noise
Noise, frequency, voltage
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
13
Computer Maintenance
Basic Electricity/Electronics
Lab 1: Using a Multimeter
Student Name: __________________________
Date: __________
Objective
Learn how to use a multimeter correctly.
Equipment
The following equipment is required for this exercise:
•
•
•
A digital multimeter for each student or team.
A manual for the multimeter.
A battery (i.e. 9v, 1.5v etc.), for each student or team to test.
NOTE: The multimeter is a sensitive piece of electronic test equipment. Be sure that
you do not drop it or throw it around. Be careful not to accidentally nick or cut the red or
black wire leads (probes). Since it is possible to check high voltages, extra care should
be taken when doing so to avoid electrical shock.
Procedures
Perform the following steps to become familiar with the handling of the multimeter.
1st Step
Insert the red and black leads (probes) into the proper jacks on the meter. The black
probe should go in the COM jack and the red probe should go in the + (plus or
positive) jack.
2nd Step
Turn on the multimeter (click/turn the on button). What model of multimeter are you
working with? _________________________________. What action must you take to
turn the meter on? _______________________________________
________________________________________________________________.
3rd Step
Switch or turn to different measurements (i.e. voltage, ohms, etc.). How many
different switch positions do the multimeter have? _____. What are they?
________________________________________________________________.
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
14
4th Step
Switch or turn the multimeter to the voltage measurement. What is the symbol for
this? ________________________________________________________.
5th Step
Put the tip of the red (positive) lead on one end of a battery (+ side), and put the tip
of the black (negative) lead on the other end of a battery. Is any number showing up
on the multimeter? __________. If not make sure you switch to the correct type of
measurement (Vol, voltage, or V). If the voltage is negative, reverse your leads.
NOTES:
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
15
Computer Maintenance
Basic Electricity/Electronics
Lab 2: Resistance Measurements
Student Name: __________________________
Date: __________
Objective
Demonstrate your ability to measure resistance and continuity with the multimeter.
Equipment
The following equipment is required for this exercise:
•
•
•
•
•
•
•
•
•
A digital multimeter for each student or team.
A 1,000 Ohm resistor for each student or team.
A 10,000 Ohm resistor for each student or team.
A pencil and paper for creating graphite paths on paper.
Cat 5 jack.
Small (0.2m or approximately 6 to 8 inches) section of Cat 5 UTP solid cable.
BNC terminated coaxial cable.
Unconnected DB9 to RJ-45 adapter.
Terminated Cat 5 UTP patch cable.
Procedures
Perform the following steps to become familiar with the handling of the multimeter.
1st Step
Move the rotary selector to the Omega symbol for Ohms (Ω) in order to measure
resistance.
Press the button that has the Ohms symbol (Ω) on it to select between resistance
measurements and continuity.
Resistance Measurements: The screen will show Ω (ohms), KΩ (kilohms =
thousands of Ohms) or MΩ (megohms = millions of Ohms). Use the Range button
to change the range of resistance to be measured based on what resistance you
expect to get. If you expect low resistance (less than 10 ohms), select a low scale
(like Ω). If you expect a high reading (over 10,000 ohms), select a high scale (like
KΩ). If the resistance reading is over the range selected, the OL or Over Limit
indicator will be displayed on the screen. The resistance setting is for measuring
exact amounts of resistance.
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
16
Continuity Measurements: The screen will show a diode symbol which is a small
black triangle pointing to a vertical bar. A diode is an electronic device that either
passes or blocks electrical current. You may see a small sound symbol next to it,
which means that when there is good continuity (no resistance) the beep will sound.
The continuity setting is used when you just want to know if there is a good path for
electricity or not and don’t care about the exact amount of resistance.
2nd Step
Check the following resistances. Turn the multimeter off when finished or battery will
drain.
Item to Measure the
resistance of:
1000 Ω Resistor
10 kΩ Resistor
Graphite marking from a
pencil on a piece of paper
Cat 5 jack
0.2 m section of Cat 5 UTP
solid cable
Touch red and black probe
contacts together
Your own body (touch the
tips of the probes with your
fingers)
BNC terminated coaxial
cable
Unconnected DB9 to RJ-45
adapter
Terminated Cat 5 UTP
cable
Set Selector and Range
Scale to:
Resistance Reading:
NOTES:
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
17
Computer Maintenance
Basic Electricity/Electronics
Lab 3: Voltage Measurements
Student Name: __________________________
Date: __________
Objective
Demonstrate your ability to measure voltage SAFELY with the multimeter.
Equipment
The following is required voltage measurement items for this exercise:
•
•
•
•
A digital multimeter for each student or team.
An assortment of batteries: A cell, C cell, D Cell, 9 Volts, 6 V lantern.
Duplex wall outlet (typical 120v).
Power supply (for laptop, or other networking electrical device).
The following is optional voltage measurement items for this exercise:
•
•
•
A lemon, with a galvanized nail stuck in one side, and a piece of uninsulated
copper wire stuck in the opposite side.
Solar cell with leads attached.
Home-made generator (wire wound around a pencil 50 times and a magnet).
Procedures
Perform the following steps to become familiar using the multimeter for voltage
measurements:
1st Step
Move the rotary selector to the V symbol for voltage (black V) in order to be able to
measure voltage.
Press the button that has the VDC and VAC symbol to select between Direct Current
(DC) or Alternating Current (AC) measurements.
Direct Current Measurements: The screen will show a V (voltage) with a series of
dots and a line over the top. There are several scales available depending on the
voltage to be measured. They start from millivolts (abbreviated mV = 1,000/th of a
volt) to voltages up to hundreds of volts. Use the Range button to change the range
of DC voltage to be measured based on what voltage you expect to measure.
Batteries (less than 15 volts) can typically be measured accurately with the VDC
scale and 0.0 range. DC voltage measurements can be used to determine if
batteries are good or if there is voltage coming out of an AC adapter (transformer or
converter) which are very common and used with hubs, modems, laptops, printers
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
18
and other peripherals. These adapters can take wall outlet AC voltage and step it
down to lower AC voltages for the device attached or can convert the AC voltage to
DC and step it down. Check the back of the adapter to see what the input (AC) and
output voltages (AC or DC) should be.
Alternating Current Measurements: The screen will show a V (voltage) with a
tilde (~) after it. This represents alternating current. There are several scales
available depending on the voltage to be measured. They start from millivolts
(abbreviated mV = 1,000/th of a volt) to voltage up to hundreds of volts. Use the
Range button to change the range of AC voltage to be measured based on what
voltage you expect to measure. Voltage from power outlets (120v or greater) can
typically be measured accurately with the VAC scale and 0.0 range. AC voltage
measurements are useful in determining if there is adequate voltage coming from an
AC outlet to power the equipment plugged in.
2nd Step
Check the following voltages. Turn the multimeter off when finished or battery will drain.
Item to Measure the
Set Selector and Range
voltage of:
Scale to:
Batteries: A cell (AA,
AAA), C cell, D cell, 9
Volts, 6 V lantern
Duplex wall outlet (typical
120v)
Power supply (converts
AC to lower AC or DC) for
laptop, mobile phone, or
other networking
electrical device.
(Optional) A lemon, with a
galvanized nail stuck in
one side, and a piece of
uninsulated copper wire
stuck in the opposite side
(Optional) Solar cell with
leads attached
(Optional) Home-made
generator (wire wound
around a pencil 50 times
and a magnet)
NOTES:
Voltage Reading:
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
19
Computer Maintenance
Basic Electricity/Electronics
Lab 4: Series Circuits
Student Name: __________________________
Date: __________
Objective
Build series circuits and explore their basic properties.
Equipment
The following is required equipment for this exercise:
•
•
•
•
•
•
A digital multimeter for each student or team.
A light switch for each student or team.
Wire cutter/stripper for each student or team.
Copper Wire.
2 light bulbs (6v) with bulb bases for each student or team.
6-Volt lantern battery for each student or team.
Procedures
Perform the following steps to explore the basic properties of series circuits:
1st Step
Measure the resistances of all devices and components except the battery.
Measure the voltage of the battery. All resistances should be less than 1 Ω (Ohm),
except the light bulbs. All the devices except the battery should register continuity
(with the tone) indicating a short circuit, or a conducting path.
Check the following resistance. Turn the multimeter off when finished or it will drain
the battery.
Item to Measure the
Resistance of:
Set Selector and Range
Scale to:
Resistance Reading:
Pieces of wire to connect
components
Light switch
Light bulbs
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
20
2nd Step
Measure the voltage of the battery, unloaded (with nothing attached to it).
Item to Measure the
voltage of:
Lantern Battery: (6 V)
with no load
Set Selector and Range
Scale to:
Voltage Reading:
3rd Step
Build a series circuit, one device at a time (use 1 battery, 1 switch, 1 bulb and
connecting wires).
Connect the battery positive lead to one end of wire and connect the negative lead to the
other wire. If the switch is turned on, the bulb should light. Disconnect one thing and
see that the circuit is broken. Did the bulb go out?
________________.
4th Step
Measure the battery voltage while the circuit is running.
The switch should be turned on and the light bulb should be lit. What was the voltage of
the battery with the light bulb on? ________________________.
5th Step
Add the second bulb in series and measure the battery voltage again.
What was the voltage of the battery with the light bulb on? _______________.
NOTES:
IT: Computer Maintenance – Basic Electricity/Electronics Plan
Copyright © Texas Education Agency, 2011. All rights reserved.
21