Lesson Plan
Course Title
Electronics
Session Title
Ohm’s Law
Performance Objective
Upon completion of this assignment, the student will be able to derive, explain,
manipulate, and calculate resistance, voltage, and current of a given circuit using Ohm’s
Law. The knowledge will be evidenced by correctly performing the procedures outlined
in the assignment sheets and lab activities and by scoring an 85 % combined score on
Ohm’s Law Exam One and Ohm’s Law Exam Two.
Specific Objectives
 Identify the three components used in Ohm’s Law.
 Derive the equivalent expressions from Ohm’s Law.
 Derive equations from Ohm’s Law to define current, voltage, and resistance.
 Explain the relationship between resistance, current flow, and voltage drop in an
electric circuit.
 Calculate the current in a circuit, given resistance and applied voltage.
 Manipulate equations and solve problems using Ohm’s Law.
Preparation
TEKS Correlations
This lesson, as published, correlates to the following TEKS. Any changes/alterations to
the activities may result in elimination of any or all of the TEKS listed.
Electronics
 130.368 (c)
o (5) The student implements the concepts and skills that form the technical
knowledge of electronics using project-based assessments. The student is
expected to:
(A) apply Ohm's law, Kirchoff's laws, and power laws; and
(C) demonstrate knowledge of the fundamentals of electronics theory.
Interdisciplinary Correlations
Algebra I
Copyright © Texas Education Agency, 2013. All rights reserved.
1

111.39 (c)
o (1) Mathematical process standards. The student uses mathematical
processes to acquire and demonstrate mathematical understanding. The
student is expected to:
(A) apply mathematics to problems arising in everyday life, society, and
the workplace;
(B) use a problem-solving model that incorporates analyzing given
information, formulating a plan or strategy, determining a solution,
justifying the solution, and evaluating the problem-solving process and
the reasonableness of the solution;
(C) select tools, including real objects, manipulatives, paper and pencil,
and technology as appropriate, and techniques, including mental math,
estimation, and number sense as appropriate, to solve problems;
(D) communicate mathematical ideas, reasoning, and their implications
using multiple representations, including symbols, diagrams, graphs, and
language as appropriate;
(E) create and use representations to organize, record, and communicate
mathematical ideas;
(F) analyze mathematical relationships to connect and communicate
mathematical ideas; and
(G) display, explain, and justify mathematical ideas and arguments using
precise mathematical language in written or oral communication.

111.39 (c)
o (4) Linear functions, equations, and inequalities. The student applies the
mathematical process standards to formulate statistical relationships and
evaluate their reasonableness based on real-world data. The student is
expected to:
(A) calculate, using technology, the correlation coefficient between two
quantitative variables and interpret this quantity as a measure of the
strength of the linear association;
(B) compare and contrast association and causation in real-world
problems; and
(C) write, with and without technology, linear functions that provide a
reasonable fit to data to estimate solutions and make predictions for
real-world problems.

111.39 (c)
o (5) Linear functions, equations, and inequalities. The student applies the
mathematical process standards to solve, with and without technology,
linear equations and evaluate the reasonableness of their solutions. The
student is expected to:
(A) solve linear equations in one variable, including those for which the
application of the distributive property is necessary and for which
Copyright © Texas Education Agency, 2013. All rights reserved.
2
variables are included on both sides.
English Language Arts and Reading, English II

110.32 (b)
o (24) Listening and Speaking/Listening. Students will use comprehension skills
to listen attentively to others in formal and informal settings. Students will
continue to apply earlier standards with greater complexity. Students are
expected to:
(A) listen responsively to a speaker by taking notes that summarize,
synthesize, or highlight the speaker's ideas for critical reflection and by
asking questions related to the content for clarification and elaboration;
and
(B) follow and give complex oral instructions to perform specific tasks,
answer questions, solve problems, and complete processes.
Copyright © Texas Education Agency, 2013. All rights reserved.
3
Occupational Correlation (O*Net –www.onetonline.org)
Job Title: Electrical and Electronics Repairers, Commercial and Industrial Equipment
O*Net Number: 49-2094.00
Reported Job Titles: Control Technician, Electronics Technician, Industrial Electrician,
Electrical Technician, Electrician, Electrical and Instrument Technician (E&I Tech),
Instrument and Electrical Technician (I&E Tech), Electrical and Instrument Mechanic,
Repair Technician, Service Technician
Tasks










Test faulty equipment to diagnose malfunctions, using test equipment or
software, and applying knowledge of the functional operation of electronic units
and systems.
Inspect components of industrial equipment for accurate assembly and
installation or for defects, such as loose connections or frayed wires.
Install repaired equipment in various settings, such as industrial or military
establishments.
Examine work orders and converse with equipment operators to detect
equipment problems and to ascertain whether mechanical or human errors
contributed to the problems.
Perform scheduled preventive maintenance tasks, such as checking, cleaning, or
repairing equipment, to detect and prevent problems.
Study blueprints, schematics, manuals, or other specifications to determine
installation procedures.
Set up and test industrial equipment to ensure that it functions properly.
Repair or adjust equipment, machines, or defective components, replacing worn
parts, such as gaskets or seals in watertight electrical equipment.
Maintain equipment logs that record performance problems, repairs,
calibrations, or tests.
Calibrate testing instruments and installed or repaired equipment to prescribed
specifications.
Soft Skills
 Repairing
 Quality Control Analysis
 Operation Monitoring
 Troubleshooting
 Critical Thinking
 Equipment Maintenance
 Active Listening
 Equipment Selection
 Complex Problem Solving
 Judgment and Decision Making
Copyright © Texas Education Agency, 2013. All rights reserved.
4
References
 Buchla, D. and Floyd, T. (2005). The science of electronics: DC/AC. Chapter four.
Upper Saddle River, NJ: Pearson Prentice Hall.
 Floyd, T. (1993). Principles of electric circuits: Electron flow version. Don Mills,
Ontario: Macmillian Publishing Co.
 Robertson, L. (1980). Basic electronics I. Stillwater, OK: Mid-American Vocational
Curriculum Consortium, Inc.
Instructional Aids
 Ohm’s Law slide presentation and notes
 Handout One- Terms and Definitions
 Handout One Answer Key
 Handout Two- The Ohm’s Law Circle; Table of Metric Prefixes
 Handout Two Answer Key
 Lab One- Use Ohm’s Law with Circuit Measurements
 Activity One- Solve Problems for an Unknown Voltage
 Activity Two- Solve Problems for an Unknown Amperage
 Activity Three- Solve Problems for an Unknown Resistance
 Activity Four- Solve Problems for an Unknown Variable
 Activities One-Four Answer Keys
 Ohm’s Law Exam One
 Ohm’s Law Exam Two
 Ohm’s Law Exam One and Two Answer Keys
Materials Needed
 Pencil and paper
 Calculator
 Breadboards and leads
 Power supplies
 Multimeters
Equipment Needed
 Computer and software
 Projector and screen
 Whiteboard
Learner Preparation
Copyright © Texas Education Agency, 2013. All rights reserved.
5



Read chapter on current in textbook
Complete lab activities
Watch slide presentation and take notes on materials
Introduction
Introduction (LSI Quadrant I)
 Say
o Electrons in a circuit behave in a certain manner that is predictable when
dealing with values of each component within the circuitry.

Ask
o Would you be able to predict for certain the values of an unknown
component given the two other components and the law that governs that
electron behavior?

Say
o A law of nature has been determined by a man named Ohm, who when given
certain conditions and values could predict the unknown value. Thus allowing
us to design any possibility that we would or could imagine. Tomorrow is
here today. Let us explore and use the law, Ohm’s Law, to explain circuit
design and our own abilities to deal with electricity.
Outline
Teachers can use the slide presentation, notes pages, and handouts in conjunction with
the following outline.
Outline (LSI Quadrant II)
Teacher Notes
I. Introduction
A. Overview
B. Terms and definitions
C. Units and the symbols
Slides 1-6
Begin Ohm’s Law slide
presentation.
Review the terms and
definition and have
students write them into
their lab notebook. The
next day, after you review
these definitions, give
students Handout OneTerms and Definitions and
have them complete it.
II. Ohm’s Law
Slide 7
Copyright © Texas Education Agency, 2013. All rights reserved.
6
A. Describe the mathematical relationship
between current, voltage, and resistance.
B. Discovered by Georg Simon Ohm, a German
physicist, in 1827.
C. Ohm spent most of his life as a high school
teacher because his work was not well
accepted by the scientific community.
D. The standard form should always be expressed
as, “current equals voltage divided by
resistance” because current is the result of
those values.
III. The Ohm’s Law Circle
A. Used as an aid to determine the different
forms of Ohm’s Law.
B. By the end of this lesson, students should
know all of the forms of Ohm’s Law.
C. Describe the use of the circle (cover the
unknown; the remaining two terms are the
equation used to find the unknown).
D. Slide 22 is a summary of the three forms of
Ohm’s Law.
Slides 8-22
Go through the slides fairly
quickly. Handout Two- The
Ohm’s Law Circle; Table of
Metric Prefixes can be
given to students to learn
to use Ohm’s Law, but it
should not be used for any
summative assessment.
IV. Visualize Ohm’s Law
A. The current (amperes) in an electric circuit
equals the electromotive force or potential
(volts) divided by the resistance (ohms).
B. E is an older, obsolete symbol for voltage
that comes from the term electromotive
force.
C. Use this slide to show the relationship
between the units, volts, amps, and ohms.
Slide 23
V. Metric prefixes
A. Use this slide and the table to review metric
prefixes.
B. Resistance values are typically large and
expressed in kiloOhms or MegaOhms.
C. Current values are typically small and expressed
in milliAmps or microAmps.
D. Centi is included primarily because centimeter
is a common unit of length. Otherwise, this
chart uses Engineering Notation.
Slide 24
This is included on
Handout Two- The Ohm’s
Law Circle; Table of Metric
Prefixes for review
purposes only, and it is not
intended to be allowed for
summative evaluation.
Copyright © Texas Education Agency, 2013. All rights reserved.
7
VI. Practice problems
A. These problems illustrate the use of the Ohm’s
Law Circle to find the equation to solve for
unknown values.
B. By the end of this lesson, (after working
through the practice problems) students
should know each of the three forms of Ohm’s
Law.
C. Each of the three forms of Ohm’s Law is
covered with an example.
D. Practice Problem One starts out with more
detail, and the level of detail is reduced for
successive problems.
E. Slide 44 shows a summary of the method the
students should be using by the end of the
lesson.
Slides 25-44
Try to be consistent about
using the procedure to
solve an equation with one
unknown, using two
known values. Hand out
Activities One-Four to
allow students to practice
finding and using Ohm’s
law.
VII. Practice problems using circuit schematics
A. Have students use only the summary method
to solve for the unknowns.
B. These slides give circuit information in the
form of circuit schematics.
C. Review schematic symbols and their meaning.
Slides 45-47
VIII. Summary
A. Given a circuit with known values, prove the
law correct.
IX. Administer Exams
A. Ohm’s Law Exam One
B. Ohm’s Law Exam Two
Slide 48
Handout Lab One- Use
Ohm’s Law with Circuit
Measurements to use
either for student practice
or for teacher
demonstration (depending
on parts and supplies
available).
Grade exams using Ohm’s
Law Exam One and Two
Answer Keys. Students
must receive 85 %
combined score on the
exams.
Application
Copyright © Texas Education Agency, 2013. All rights reserved.
8
Guided Practice (LSI Quadrant III)
 The teacher will use materials listed in the lab activities to instruct how to read,
measure with, and record data needed.
 The students will observe, ask questions, and analyze the demonstration to be
presented by the teacher.
Independent Practice (LSI Quadrant III)
 The student will try to replicate the lab activities.
 The student will answer the discussion questions on the Lab One- Use Ohm’s Law
with Circuit Measurements handout.
 The student will answer the questions in the four activity handouts and turn in
for evaluation:
o Ohm’s Law Activity One- Solve Problems for an Unknown Voltage
o Ohm’s Law Activity Two- Solve Problems for an Unknown Amperage
o Ohm’s Law Activity Three- Solve Problems for an Unknown Resistance
o Ohm’s Law Activity Four- Solve Problems for an Unknown Variable
Summary
Review (LSI Quadrants I and IV)
Review the student’s data sheets to evaluate if individual or small group activity is the
best approach for learning.
Evaluation
Informal Assessment (LSI Quadrant III)
 The teacher will monitor each person or small group as they individually work to
complete the assignments.
 If re-teach is needed on any information or procedure, all those involved will
stop and participate in the re-teach.
Formal Assessment (LSI Quadrant III, IV)
 The student will be assessed by the accuracy of the completed assignments. Use
the Activities One-Four Answer Keys to grade them.
 The teacher will divide the final assessment into two parts.
o Two formal exams: Exam One and Exam Two (written). Use the Exam One
Answer Key and the Exam Two Answer Key to grade them.
o A measurement test of a series of exercises using the breadboards,
power supplies, and assorted loads or lamps to measure current, voltage,
resistors, accurately.
Copyright © Texas Education Agency, 2013. All rights reserved.
9
Extension
Extension/Enrichment (LSI Quadrant IV)
 The use of the multimeter to measure accurately current, voltage, and resistance
becomes a vital part of the technical problem-solving skills needed in the world
of work.
 Thinking through a problem to arrive at the answer and the persistency to work
past their frustrations tempers a student’s character.
 There are points in the lab experience where the student takes some part in
leadership skills; leading or following creates a sense of accomplishment that
adds to the character of the involved students. Cognitive and leadership skills go
hand in hand with solving life’s roadblocks.
Copyright © Texas Education Agency, 2013. All rights reserved.
10
Name: ____________________________________ Class: ________ Date ___/___/___
Terms and Definitions Handout One
Define the following terms.
1.
Voltage:
2.
Current:
3.
Resistance:
4.
Electrical power:
5.
Ohm’s Law:
6.
Directly proportional:
7.
Inversely proportional
Give the units and symbols for the following.
8.
Voltage:
9.
Current:
10.
Resistance:
11.
Electrical power:
Copyright © Texas Education Agency, 2013. All rights reserved.
11
Terms and Definitions Handout One Answer Key
Define the following terms.
1.
Voltage: electrical potential; an electrical pressure created by the buildup of
charge
2.
Current: the flow or movement of electrons
3.
Resistance: opposition to current flow
4.
Electrical power: the rate of electrical energy used in a circuit
5.
Ohm’s Law: a formula describing the mathematical relationship between
voltage, current, and resistance
6.
Directly proportional: having a constant ratio
7.
Inversely proportional: having a constant but inverse ratio
Give the units and symbols for the following.
8.
Voltage: volts, v
9.
Current: amps, I
10.
Resistance: Ohms, Ω
11.
Electrical power: watts, P
Copyright © Texas Education Agency, 2013. All rights reserved.
12
Handout Two
The Ohm’s Law Circle
Table of Metric Prefixes
Copyright © Texas Education Agency, 2013. All rights reserved.
13
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Lab One- Use Ohm’s Law with Circuit Measurements
Equipment and materials_________________________________________________

Multimeter or ammeter and voltmeter with leads

DC Power Source

One 3.3-K ohm resistor and one 1-K ohm resistor

Switch, SPST
Procedure______________________________________________________________
1. Connect the DC power supply to one 3.3-K ohm resistor in series with an ammeter
(Figure 1)
Figure 1
2. Turn on the power supply and adjust for a 3 volt output
3. Close the switch, then read and record the ammeter indication in the data table
(Table 1)
Data Table
OBSERVED
__________
E
I
R
COMPUTED
___________
E
I
R
Step 3
3v ____ 3.3 KΩ
___ ___ ___
Step 5
6v ____ 3.3 KΩ
___ ___ ___
Step 9
3v ____ 4.3 KΩ
___ ___ ___
Step 12
____ ____ 3.3 KΩ
___ ___ ___
Step 13
____ ____ 3.3 KΩ
___ ___ ___
Step 14
____ ____ 3.3 KΩ
___ ___ ___
Copyright © Texas Education Agency, 2013. All rights reserved.
14
Name: ____________________________________ Class: ________ Date ___/___/___
4. Increase the output of the power supply to 6 volts
5. Read the ammeter indication and record on the data table
6. Compare the current observed in Step 3 with that observed in Step 5
NOTE: With no change in resistance, an increase in voltage results in (increase)
(decrease) of circuit current
7. Turn off the power supply and install both resistors in series with the ammeter
(Figure 2)
Figure 2
8. Turn on the power supply and adjust for a 3 volt output
9. Read the ammeter indication and record in the data table
10. Compare the current observed in Step 9 with that observed in Step 3
NOTE: With no change in voltage, does an increase in resistance result in (increase)
or (decrease) of circuit current?
11. Connect a voltmeter across the 3.3-K ohm resistor
12. Read the voltmeter indication and record on the data table
13. Observe the ammeter indication and adjust the power supply for a slight increase in
the circuit current
14. Read the voltmeter indication and record on the data table
15. Compare the voltage observed in Step 12 with that observed in Step 14
NOTE: With no change in resistance, does an increase in current result in (increase)
or (decrease) of voltage?
16. Use the observed values for E, I, and R and compare these values using Ohm’s Law
17. Record your results in the spaces provided in the data table
Copyright © Texas Education Agency, 2013. All rights reserved.
15
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity One- Solve Problems for an Unknown Voltage
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
Ohms
Amps
Volts
1.
6
20
_____
2.
60
4
_____
3.
2.5
9.6
_____
4.
3
5
_____
5.
0.16
75
_____
6.
5 x 103
2 x 10-3
_____
7.
10 x 103
1 x 10-6
_____
8.
1M
8µ
_____
9.
2K
2m
_____
10.
1
1
_____
Copyright © Texas Education Agency, 2013. All rights reserved.
16
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity Two- Solve Problems for an Unknown Amperage
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
Volts
Ohms
Amps
1.
240
12
_____
2.
110
11
_____
3.
440
20
_____
4.
120
30
_____
5.
24
3
_____
6.
5 x 10-6
1
_____
7.
12
1
_____
8.
2 x 10-3
4 x 10-3
_____
9.
20 Kv
5 x 10+6
_____
10.
1 Kv
0.5 x 106
_____
Copyright © Texas Education Agency, 2013. All rights reserved.
17
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity Three- Solve Problems for an Unknown Resistance
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
Volts
Amps
Ohms
1.
240
4
_____
2.
24
9.6
_____
3.
12
5
_____
4.
230
5
_____
5.
24
8
_____
6.
24
2ma
_____
7.
12
3µa
_____
8.
1 Kv
5 ma
_____
9.
1x 103
10.
2.5x 103
0.5x 10-3
_____
5x 10-3
_____
Copyright © Texas Education Agency, 2013. All rights reserved.
18
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity Four- Solve Problems for an Unknown Variable
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
1.
1600 Ω
2.
24v
9.6 Ω
_____
3.
63000 µa
34 Kv
_____
4.
6 KΩ
36 Kv
_____
5.
40 MΩ
8 µa
_____
6.
24 Kv
2 ma
_____
7.
12 MΩ
8.
9.
10.
25 ma
_____
3µa
_____
1 Kv
50 ma
_____
1x 103 v
0.5x 10-3 a
_____
2.5x 103 Ω
5x 10-3 a
_____
Copyright © Texas Education Agency, 2013. All rights reserved.
19
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity One- Solve Problems for an Unknown Voltage Key
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
Ohms
Amps
Volts
1.
6
20
E = IR= 6 x 20 = 120 volts
_120_
2.
60
4
E = IR= 60 x 4 = 240 volts
_240_
3.
2.5
9.6
E = IR= 2.5 x 9.6 = 24 volts
__24_
4.
3
5
E = IR= 3 x 5 = 15 volts
__15_
5.
0.16
75
E = IR= 0.16 x 75 = 12 volts
__12_
6.
5 x 103
2 x 10-3
E = IR= 5000 x .002 = 10 volts
__10_
7.
10 x 103
1 x 10-6
E = IR= 1000 x .000001 = .001 volts
_.001_
8.
1M
8µ
E = IR= 100000 x .000008 = 8 volts
___8_
9.
2K
2m
E = IR= 2000 x .002 = 4 volts
___4_
10.
1
1
E = IR= 1 x 1 = 1 volts
___1_
Copyright © Texas Education Agency, 2013. All rights reserved.
20
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity Two- Solve Problems for an Unknown Amperage Key
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
Volts
Ohms
Amps
1.
240
12
I = E/R = 240/ 12 = 20 amps
__20___
2.
110
11
I = E/R = 110/ 11 = 10 amps
__10___
3.
440
20
I = E/R = 440/ 20 = 20 amps
__20___
4.
120
30
I = E/R = 120/ 30 = 4 amps
___4___
5.
24
3
I = E/R = 24/ 3 = 8 amps
___8___
6.
5 x 10-6
1
I = E/R = .000005/ 1 = .000005 amps
.000005
7.
12
1
I = E/R = 12/ 1 = 12 amps
__12___
8.
2 x 10-3
4 x 10-3
I = E/R = .002/ .004 = .5 amps
__.5___
9.
20 Kv
5 x 10+6
I = E/R = 20000/ 500000 = 0.04 amps
_0.04__
10.
1 Kv
0.5 x 106
I = E/R = 1000/ 50000 = 0.02 amps
_0.02__
Copyright © Texas Education Agency, 2013. All rights reserved.
21
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity Three- Solve Problems for an Unknown Resistance Key
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
Volts
Amps
Ohms
1.
240
4
R= E/I = 240/ 4 = 60 Ω
__60___
2.
24
9.6
R= E/I = 24 / 9.6 = 2.5 Ω
_2.5___
3.
12
5
R= E/I = 12/ 5 = 2.4 Ω
_2.4___
4.
230
5
R= E/I = 230/ 5 = 46 Ω
__46___
5.
24
8
R= E/I = 24/ 8 = 3 Ω
___3___
6.
24
2ma
R= E/I = 24/ .002 = 12000 Ω
12000__
7.
12
3µa
4000000
R= E/I = 12/ 0.000003 = 4000000 Ω
8.
1 Kv
5 ma
R= E/I = 1000/ 0.005 = 200000 Ω
200000_
9.
1x 103
0.5 x 10-3
R= E/I = 1000/ 0.0005 = 60 Ω
2000000
10.
2.5x 103
5 x 10-3
R= E/I = 2500/ 0.005 = 60 Ω
500000_
Copyright © Texas Education Agency, 2013. All rights reserved.
22
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Activity Four- Solve Problems for an Unknown Variable Key
Directions
State the appropriate formula, fill in variables, and answer with appropriate unit tag.
Example
Given current of 16 ma and resistance of 20 KΩ
E=IR= (16ma) (20KΩ) = 320 v
Problems
1.
1600 Ω
25 ma
E = IR= 1600 x 0.025 = 40 volts
40 volts___
2.
24v
9.6 Ω
I = E/R = 24/ 9.6 = 2.5 amps
2.5 amps__
3.
63000 µa
34 Kv
R= E/I = 34000/ 0.063 = 539.68 Ω
539.68 Ω__
4.
6 KΩ
36 Kv
6 amps___
I = E/R = 36000/ 6000 = 6 amps
5.
40 MΩ
8 µa
E = IR= 0.000008 x 40000000 = 320 volts
320 volts__
6.
24 Kv
2 ma
R= E/I = 24000/ 0.002 = 12000000 Ω
12000000Ω
7.
12 MΩ
3µa
E = IR= 12000000 x .000003 = 36 volts
36 volts___
8.
1 Kv
50 ma
R= E/I = 1000/ 0.05 = 20000 Ω
20000Ω___
9.
1x 103 v
0.5x 10-3 a
R= E/I = 1000/ 0.0005 = 2000000Ω
2000000Ω_
10.
2.5x 103 Ω
5x 10-3 a
E = IR= 0.005 x 2500 = 1 volts
12.5 volts__
Copyright © Texas Education Agency, 2013. All rights reserved.
23
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Exam One
Match the terms to the correct definitions.
1. Ampere
A The unit of measurement of electrical current
2. Ohm
B Unit of measure for the opposition to electron flow in a circuit
3. Volt
C Unit of measure of potential difference
4. Watt
D Unit of measure of power
Match the symbols or abbreviations with their correct definition.
5. R
A Symbol for unit of measurement for power
6. E
B Symbol for unit of measurement for electron flow
7. W
C Symbol for unit of measurement for potential differences
8. I
D Symbol for unit of measurement for opposition to electron flow
Solve the following problems.
9. Given that the total load for the circuit is 455Ω and the applied voltage is 40 volts, find the
current.
A 11.375 ma
B 1.1375 a
C 87.912 ma
D 879.12 µa
10. Given the following closed loop circuit condition, what is the total resistance in this circuit?
The current is 32.5 ma, the circuit of four loads different resistance values, and the applied
voltage is 32.5 volts.
A 1000Ω
B 2a
C 32.5 v
D 575 Ω
Copyright © Texas Education Agency, 2013. All rights reserved.
24
Name: ____________________________________ Class: ________ Date ___/___/___
11. If the following loads have current of RT 24000Ω with an applied voltage of 25 volts, what is
the current to this circuit?
A 1041.6 µa
B 243 ma
C 1.0416 ma
D both a and c
12. Given the following variables, I= 125µa and the total resistance = 4MΩ, what is the voltage
applied?
A 45 volts
B 500 volts
C 50 volts
D 450 volts
13. Which symbol indicates 10-6?
A m
B p
C µ
D K
14. Given the following values, applied voltage is 6 volts and the total resistance is 560 KΩ, find
the unknown variable.
A 10.71 ma
B 171.7 ma
C 112 a
D 11.2 ma
15. Solve for unknown voltage when I= 2 milliamps and R= 3 kilo-ohms. E= ____
A 66.67 volts
B 1.5 volts
C 6 volts
D .667 volts
16. Solve for unknown current when E= 12 volts and R= 12 K ohms. I= _____
A 1.44 ma
B 144 a
C 1 ma
D 24 ma
Copyright © Texas Education Agency, 2013. All rights reserved.
25
Name: ____________________________________ Class: ________ Date ___/___/___
17. Solve for unknown resistance when E= 110 volts and I= 2 amperes. R= _____
A 50 Ω
B 18.18 Ω
C 220 Ω
D 55 Ω
18. Solve for unknown voltage when I= 16 milliamps and R= 8 megaohms. E= ____
A 128 volts
B 128 Kvolts
C 200 volts
D 24 volts
19. Solve for unknown current when E= 25 volts and R= 5 M ohms. I= _____
A 5 µa
B 5 ma
C 2 µa
D 2 ma
20. Solve for unknown resistance when E= 22 volts and I= 2µa. R= _____
A 44 MΩ
B 11 MΩ
C 33 KΩ
D 44 KΩ
21. Given the following closed loop circuit condition, what is the total resistance in this circuit?
The current is 325 µa, the circuit of four loads different resistance values, and the applied
voltage is 120 volts.
A 36923 Ω
B 369.23 ma
C 16918 Ω
D 445 MΩ
22. Given the following values, applied voltage is 12 volts and the total resistance is 5.60 MΩ,
find the unknown variable.
A 2.1 ma
B 17.6 ma
C 2.1µ a
D 67.2 µa
Copyright © Texas Education Agency, 2013. All rights reserved.
26
Name: ____________________________________ Class: ________ Date ___/___/___
23. Given the following values, current is 6 µa and the total resistance is 560 MΩ, find the
unknown variable.
A 93.33 volts
B 3360 volts
C 336 volts
D 33.6 volts
Copyright © Texas Education Agency, 2013. All rights reserved.
27
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Exam One Key
Match the terms to the correct definitions.
1. Ampere
A
A The unit of measurement of electrical current
2. Ohm
B
B Unit of measure for the opposition to electron flow in a circuit
3. Volt
C
C Unit of measure of potential difference
4. Watt
D
D Unit of measure of power
Match the symbols or abbreviations with their correct definition.
5. R
D
A Symbol for unit of measurement for power
6. E
C
B Symbol for unit of measurement for electron flow
7. W
A
C Symbol for unit of measurement for potential differences
8. I
B
D Symbol for unit of measurement for opposition to electron flow
Solve the following problems.
9. Given that the total load for the circuit is 455Ω and the applied voltage is 40 volts, find the
current.
A 11.375 ma
B 1.1375 a
C 87.912 ma
D 879.12 µa
10. Given the following closed loop circuit condition, what is the total resistance in this circuit?
The current is 32.5 ma, the circuit of four loads different resistance values, and the applied
voltage is 32.5 volts.
A 1000Ω
B 2a
C 32.5 v
D 575 Ω
Copyright © Texas Education Agency, 2013. All rights reserved.
28
Name: ____________________________________ Class: ________ Date ___/___/___
11. If the following loads have current of RT 24000Ω with an applied voltage of 25 volts, what is
the current to this circuit?
A 1041.6 µa
B 243 ma
C 1.0416 ma
D both A and C
12. Given the following variables, I = 125µa and the total resistance = 4MΩ, what is the voltage
applied?
A 45 volts
B 500 volts
C 50 volts
D 450 volts
13. Which symbol indicates 10-6?
A m
B p
C µ
D K
14. Given the following values, applied voltage is 6 volts and the total resistance is 560 KΩ, find
the unknown variable.
A 10.71 ma
B 171.7 ma
C 112 a
D 11.2 ma
15. Solve for unknown voltage when I= 2 milliamps and R= 3 kilo-ohms. E= ____
A 66.67 volts
B 1.5 volts
C 6 volts
D .667 volts
16. Solve for unknown current when E= 12volts and R= 12 K ohms. I= _____
A 1.44 ma
B 144 a
C 1 ma
D 24 ma
Copyright © Texas Education Agency, 2013. All rights reserved.
29
Name: ____________________________________ Class: ________ Date ___/___/___
17. Solve for unknown resistance when E= 110 volts and I= 2 amperes. R= _____
A 50 Ω
B 18.18 Ω
C 220 Ω
D 55 Ω
18. Solve for unknown voltage when I=16 milliamps and R= 8 megaohms. E= ____
A 128 volts
B 128 Kvolts
C 200 volts
D 24 volts
19. Solve for unknown current when E= 25 volts and R= 5 M ohms. I= _____
A 5 µa
B 5 ma
C 2 µa
D 2 ma
20. Solve for unknown resistance when E= 22 volts and I= 2µa. R= _____
A 44 MΩ
B 11 MΩ
C 33 KΩ
D 44 KΩ
21. Given the following closed loop circuit condition, what is the total resistance in this circuit?
The current is 325 µa, the circuit of four loads different resistance values, and the applied
voltage is 120 volts.
A 36923 Ω
B 369.23 ma
C 16918 Ω
D 445 MΩ
22. Given the following values, applied voltage is 12 volts and the total resistance is 5.60 MΩ,
find the unknown variable.
A 2.1 ma
B 17.6 ma
C 2.1µ a
D 67.2 µa
Copyright © Texas Education Agency, 2013. All rights reserved.
30
Name: ____________________________________ Class: ________ Date ___/___/___
23. Given the following values, current is 6 µa and the total resistance is 560 MΩ, find the
unknown variable.
A 93.33 volts
B 3360 volts
C 336 volts
D 33.6 volts
Copyright © Texas Education Agency, 2013. All rights reserved.
31
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Exam Two
1. State Ohm’s Law. (5pts)
2. Draw the circular expression of Ohm’s Law. (4pts)
3. List three uses of Ohm’s Law in any order. (2pts each)
1. _________________________________________
2. _________________________________________
3. _________________________________________
The following problems are four points each: state formula (1), fill in values with labels (1), give
the numeric answer (1), and provide the proper tag (1).
Given
Answer
4.
37 KΩ
10 µa
__________
5.
2 ma
57 volts
__________
6.
24 volts
250 KΩ
__________
7.
100 µa
35 MΩ
__________
8.
12.5 volts
13 µamps
__________
Copyright © Texas Education Agency, 2013. All rights reserved.
32
Name: ____________________________________ Class: ________ Date ___/___/___
Ohm's Law
Exam Two Key
1. State Ohm’s Law. (5pts)
The current (amperes) in an electric circuit equals the electromotive force or potential
differences (volts) divided by the resistance (ohms).
2. Draw the circular expression of Ohm’s Law. (4pts)
3. List three uses of Ohm’s Law. (2pts each)
1. __Used to calculate voltage ___E = IR_______
2. __Used to calculate current ___I= E / R______
3. __Used to calculate resistance _R= E / I______ (any order)
The following problems are four points each: state formula (1), fill in values with labels (1), give
the numeric answer (1), and provide the proper tag (1).
Given
Answer
4.
37 KΩ
10 µa
E = IR = .00001 a x 37000 Ω = 0.37 v_
_0.37__volts
5.
2 ma
57 volts
R= E / I = 57 / .002 = 28500 Ω_______
28500_ Ω__
6.
24 volts
250 KΩ
I= E / R = 24 / 250000 = 96 µamps____
_96_µamps
7.
100 µa
35 MΩ
E = IR = .0001 x 35000000 = 3500 volts
_3500 volts
8.
12.5 volts
13 µamps
R= E / I = 125 / .000013 = 9615385 Ω_
9615385 Ω
Copyright © Texas Education Agency, 2013. All rights reserved.
33