Lesson Plan. Course Title: Concepts of Engineering and Technology Session Title: Basic Electricity and Electronics: Module 1 - Basic Electricity

Transcription

1 Lesson Plan Course Title: Concepts of Engineering and Technology Session Title: Basic Electricity and Electronics: Module 1 - Basic Electricity Performance Objective: After completing this lesson, the student will be able to demonstrate their understanding of basic electricity and electronic fundamentals through satisfactory performance on the Basic Electricity and Electronics Quiz. Specific Objectives: The student is able to: Recall how charge creates electrical forces Review basic atomic theory within a new framework for understanding electricity Define the basic electrical quantities Create the foundation for understanding transistors and digital electronics Recall that sound is a pressure wave that can be produced by a vibrating speaker cone Work problems involving Ohm s Law Preparation TEKS Correlations: This lesson, as published, correlates to the following TEKS. Any changes/alterations to the activities may result in the elimination of any or all of the TEKS listed. Concepts of Engineering and Technology: (c)(1)(b)(c)(d)...identify the inputs, processes, and outputs associated with technological systems;...describe the difference between open and closed systems;...describe how technological systems interact to achieve common goals; (c)(6)(a)(b)(c)(d)...identify and describe the fundamental processes needed for a project, including design and prototype development;...identify the chemical, mechanical, and physical properties of engineering materials;...use problem-solving techniques to develop technological solutions;...use consistent units for all measurements and computations; (c)(8)(a)(b)(c)(d)(e)...describe applications of process control and automation systems;...describe career opportunities in process control and automation systems;...apply design concepts to problems in process control and automation systems;...identify fields related to process control and automation systems; and...identify emerging issues in process control and automation systems. Copyright Texas Education Agency, All rights reserved. 1

2 Interdisciplinary Correlations: Algebra I: (b)(1)(a)(b)(c)(d)(e)...describe independent and dependent quantities in functional relationships;...gather and record data and use data sets to determine functional relationships between quantities;...describe functional relationships for given problem situations and write equations or inequalities to answer questions arising from the situations;...represent relationships among quantities using concrete models, tables, graphs, diagrams, verbal descriptions, equations, and inequalities; and...interpret and make decisions, predictions, and critical judgments from functional relationships (b)(3)(a)(b)...use symbols to represent unknowns and variables; and...look for patterns and represent generalizations algebraically (b)(4)(a)(b)...find specific function values, simplify polynomial expressions, transform and solve equations, and factor as necessary in problem situations;...use the commutative, associative, and distributive properties to simplify algebraic expressions; Integrated Physics and Chemistry: (b)(5)(c)(f) demonstrate that moving electric charges produce magnetic forces and moving magnets produce electric forces; and evaluate the transfer of electrical energy in series and parallel circuits and conductive materials (b)(6)(b)(d) relate chemical properties of substances to the arrangement of their atoms or molecules; and relate the physical and chemical behavior of an element, including bonding and classification, to its placement on the periodic table. Teacher Preparation: Review basic DC theory and Ohm s law. The section on Basic Electricity is covered in the first 22 slides. The next section covering Basic Electronics is much longer, taking 38 slides. We have used a CD player as a real world example of how we use electricity and electronics. There are plenty of other devices (that students use) that can be used. Tell students if they want to understand how these work they must understand some of the basics of electricity and electronics. Try to read ahead and relate some of the information given in the basics to the Copyright Texas Education Agency, All rights reserved. 2

3 more advanced electronics of the next section, Basic Electronics. The coverage of the CD is a little spotty at times, but do your best to keep some kind of focus on applications of the electricity and electronics covered. References: Gerrish, H. & Dugger, W. Jr., & Roberts, R. Electricity and Electronics. Goodheart-Willcox. Karsnitz, J. & Hutchinson, J., & O Brien, S. (2008). Engineering Design and Introduction. Cengage Learning Inc./Delmar. Use Wikipedia as a resource. Instructional Aids: 1. Module 1 Basic Electricity PPT presentation 2. Basic Electricity and Electronics problem worksheet and key 3. Basic Electricity and Electronics terms and definitions handout 4. Basic Electricity and Electronics quiz 5. Basic Electricity and Electronics quiz key Materials Needed: 1. CD-ROM disk 2. Paper 3. Pen or pencil Equipment Needed: 1. Computer with access to Internet 2. Projector 3. CD player 4. Unshielded speaker Learner Preparation: Students need a basic understanding of algebra in order to solve equations and define variables. Introduction Introduction (LSI Quadrant I): SAY: Today we are going to start learning about the basics of electricity and electronics. ASK: Does anyone know where electricity comes from? (conversion of energy from one form to another, like chemical to electrical or mechanical to electrical) SHOW: Here is a wire. SAY: This wire is a solid. However, there are particles in here that move and allow electrical current to flow. ASK: Does anyone know what particle in this wire allows electricity to flow? (the electrons) SHOW: A CD-ROM disk Copyright Texas Education Agency, All rights reserved. 3

4 ASK: Does anyone here know how this really works? SAY: There are tiny pits and spaces that a laser reads as binary one s and zero s. The one s and zero s are in a form of binary code that represents the music. ASK and SHOW: A CD player. This player converts the binary code into music. Does anyone here know how this works? SAY: This converts the code to a voltage signal using principles of the audible hearing frequency range. SAY: Frequencies from 20 to 20 thousand cycles per second are produced by sending the signal out as a voltage 44 thousand 100 times per second. Outline Outline (LSI Quadrant II): Instructors can use the PowerPoint presentation, slides, handouts, and note pages in conjunction with the following outline. MI Outline Notes to Instructor I. Basic Electricity and Electronics - Speakers and CD A. A speaker is like a DC motor, converting electrical energy into mechanical energy, and can be used as an introduction to that topic. B. A microphone is like an AC generator converting mechanical energy (sound pressure waves) into electrical energy. C. Lower frequencies require more sound pressure variation, higher frequencies require less. D. The more sound pressure needed, the more energy needed. Bass requires far more energy than treble. E. All signal information uses the same 16 bits per channel, regardless of the amplitude (unlike MP3 data). F. Changes in frequency are not a part of the recorded signal itself but are the result of signal changes from sample to sample. Start with slide one of Basic Electricity and Electronics: Module 1 Basic Electricity PowerPoint presentation. Speakers and CD audio can require much more description than given. We are trying to hook the students by using a real world example. Devices that convert energy from one form to another are called transducers. Use Wikipedia as a resource. II. Basic Electricity and Electronics A. The first major concept is that electrons do the work in an electrical circuit. B. This provides a great framework to review basic atomic structure. C. Electrons must be separated from the atom both to flow for current and to build up the charge needed to provide the force (voltage) used in an electric circuit The basic electricity and electronics section starts on slide 9. This is important material that needs to be covered so students can understand the operation of the transistor and the Copyright Texas Education Agency, All rights reserved. 4

5 circuits to follow.. III. Like charges repel, unlike charges attract A. This is called the weak electrical force. B. Electrons have a negative charge. C. Protons have a positive charge. D. Electrons are attracted to the protons in the nucleus. E. Protons are attracted to protons in the nucleus through the strong electrical force. Continue with PPT presentation. IV. The electron configuration creates the similar properties that allow groups of elements to form the familiar periodic table of the elements A. Electrons orbit the nucleus in shells or layers. B. Different layers can have different numbers of electrons. C. The most electrons an atom can have in an outer shell is 8. D. 8 electrons in an outer shell creates a stable atom and a stable molecule, or combination of atoms. E. Atoms combine into molecules to get 8 electrons in the outer shell, which are shared. There are 3 forms of bonding: Ionic, covalent, and metallic. V. Basic digital principles and introducing the next topic, transistors. The last slide in this section discusses some basic digital principles and concludes by introducing the next topic, transistors. Introducing digital is a kind of a teaser, they are going to have to get through the section on transistors before we start to cover digital and logic in more detail. Copyright Texas Education Agency, All rights reserved. 5

6 VI. As an extension/enrichment activity, you can end this section by asking students to do further research on CD audio. A. Students can do a research paper and/or a presentation on CD audio. One particularly interesting feature is that even though CD audio was advanced technology for its time, it relied on analog signal principles the same way that AM or FM radio does. B. Advanced students can do research on MP3 technology. C. How does digital radio or the new HD TV broadcasts differ from older analog transmission? You may want to break out of the lecture mode by having students do their own research. MP3 technical details are particularly complex, and not easily found on the Internet. Verbal Linguistic Logical Mathematical Visual Spatial Musical Rhythmic Bodily Kinesthetic Intrapersonal Interpersonal Naturalist Existentialist Application Guided Practice (LSI Quadrant III): Question and answer with definitions. Example: What is the definition of voltage? What is the definition of current? What is the definition of resistance? What is the formula for Ohm s Law? What is the symbol for voltage (V)? What is the symbol for current? (I) What are the three fundamental particles in an atom? Independent Practice (LSI Quadrant III): Have students study how a speaker works. Wikipedia is a good source. Have students work problems involving Ohm s law. Students should work a number of problems, solving for each of the three quantities. Summary Review (LSI Quadrants I and IV): Question: Can you see a speaker cone move for high frequency sounds? What about for low frequencies? How does sound volume relate to speaker cone movement? Answer: No and yes. However, you can feel the speaker move for the high frequency signals. What does this say about our sense of touch vs. vision? Touch the speaker gently, by the way. This may be a good way to introduce the concepts of amplitude vs. frequency, and power required to produce. Copyright Texas Education Agency, All rights reserved. 6

7 Question: Can you see electricity? How do you know it s there? Can you feel it? Answer: You cannot see it, but you can see many of its effects, like light and heat. For safety, you never want to touch an electrical circuit. Use a multimeter or other testing device. Question: What element has 6 protons? What element has 23 protons? What element has 23 neutrons? Answer: Carbon, Vanadium, and we can t tell without more information (like atomic weight, not atomic number). Actually, no element. Perhaps an isotope of Scandium. Question: Ohm s Law uses what 3 quantities? Answer: Voltage, current, resistance. Question: What are some other forms of energy we can convert to electrical energy? Answer: Thermal, light, pressure Question: Why do we use electricity instead of other forms of energy? Answer: We do use other forms of energy, but electricity can be converted into those other forms, and electricity is easy to transmit efficiently while many of the other forms of energy are not as easy to transmit. Evaluation Informal Assessment (LSI Quadrant III): Students should write out definitions, and complete Problems Worksheet. Formal Assessment (LSI Quadrant III, IV): Basic Electricity and Electronics Quiz. Extension Extension/Enrichment (LSI Quadrant IV): Students can do further research on CD audio. Students that are interested can do research on speaker operation, design, and optimization (woofer, midrange, tweeter). One interesting subject is how MP3 technology works, and how it is different from CD audio. Wikipedia is a good source, but a better source is ( This would be a great topic for a presentation or a research paper. Copyright Texas Education Agency, All rights reserved. 7

8 Basic Electricity and Electronics Module One Terms and Definitions 1. Volt is a potential difference between two points. 2. Energy - is the fundamental ability to do work. 3. KW-Hr - is a unit of energy. 4. Electrical load - is any resistive element connected to a power supply. 5. Joule per second - is a unit of power. 6. Sound - is the movement of air molecules. 7. Current is the movement of electrons. 8. Voltage - is force created by the buildup of charge. 9. Resistance is the opposition to current flow. 10.Ohm is the unit of resistance. 11.Coulomb is the unit of electrical charge. Copyright Texas Education Agency, All rights reserved. 8

9 Basic Electricity and Electronics Module One Quiz 1. Which device opposes current? a. Resistor b. Capacitor c. Inductor d. Coil 2. Which of the following is a control device? a. Resistor b. Switch c. Fuse d. Ground 3. What is the most common material a resistor is made from? a. Silicon b. Metal film c. Carbon d. Ceramics 4. Which of the following is the symbol for current? a. A b. V c. Ω d. I 5. How much resistance does an insulator have? a. Zero b. Some c. A lot d. Infinite 6. Different elements always have different numbers of? a. Protons b. Neutrons c. Atoms d. Atomic shells Copyright Texas Education Agency, All rights reserved. 9

10 7. A volt is a/an: a. Potential difference between two points b. Unit of charge on an electron c. Rate of flow of charge d. Opposition to current flow 8. How many forms of Ohm s Law are there? a. One b. Two c. Three d. Four 9. Energy is: a. The fundamental ability to do work b. The rate at which energy is used c. The amount when one joule is used in one second d. The maximum amount of power dissipated without damage 10. A KW-Hr is a unit of: a. Energy b. Power c. Heat d. Voltage times current 11. An electrical load is: a. Any weight being carried b. The amount of horsepower in a circuit c. Any resistive element connected to a power supply d. Taking more than four classes a semester 12. Which of the following is a unit of power? a. Joule b. Joule per second c. Joule-second d. Volt-ohm Copyright Texas Education Agency, All rights reserved. 10

11 13. When the voltage across a resister is doubled, the current will: a. Triple b. Halve c. Double d. Not change 14. When the resistance in a circuit is doubled, the current will: a. Triple b. Halve c. Double d. Not change 15. Sound is the movement of: a. Air molecules b. Electrons c. Protons d. Electricity 16. A speaker acts similar to a: a. Generator b. Motor c. Transistor d. Battery 17. What performs the work in an electric circuit? a. Heat b. Voltage c. A resistor d. Current 18. What is the definition of current? a. The movement of electrons b. Force created by the buildup of charge c. Force times distance d. A twisting or rotary force 19. What is the definition of voltage? a. The movement of electrons b. Force created by the buildup of charge c. Force times distance d. A twisting or rotary force Copyright Texas Education Agency, All rights reserved. 11

12 20. What is resistance? a. The interaction of two magnetic fields b. Conversion of mechanical energy into electrical energy c. An imbalance between electrons and protons d. The opposition to current flow 21. What is the formula for Ohm s Law? a. P = V I b. I = V / R c. F = M A d. I = V 2 R 22. CD data represents: a. Signal frequency as a binary code b. Signal amplitude as a binary code c. Cosine transform coefficients d. Data reduction through elimination of masked signals 23. What is the sample rate of CD audio? a. 20,000 samples/second b. 128 Kbytes per second c. 44,100 samples per second d. 32 bits per second 24. The unit of resistance is the: a. Coulomb b. Joule c. Ampere d. Ohm 25. The unit of electrical charge is the: a. Coulomb b. Joule c. Ampere d. Ohm Copyright Texas Education Agency, All rights reserved. 12

13 26. A circuit has a 12 V power supply and a 1 kω resistor. What is the current? 27. A circuit has a 42 kω resistor and 8 ma of current. What is the voltage? 28. A circuit has 520 milli amps of current and 240 volts. What is the resistance? 29. List some of the reasons electricity is so useful. Copyright Texas Education Agency, All rights reserved. 13

14 30. A circuit has 470 kω and 16 V. What is the current? 31. I = 145 ma, R = 10 MΩ. V =? 32. In the following circuit calculate current and voltage drops. R 1 = 2 KΩ 12V R2 = 4 KΩ Copyright Texas Education Agency, All rights reserved. 14

15 33. In the following circuit, calculate total current and total resistance. 18V R1 = 2kΩ R2 = 4kΩ 34. In the following circuit, what is R 1? R 1 12V I = 1 ma R2 = 4 KΩ 35. A power supply consumes 320 mw in order to supply 288 mw to the load. What is the efficiency? 36. What is R 2 in the following circuit? I T = 12 ma 18V R1 = 2kΩ R2 =? Copyright Texas Education Agency, All rights reserved. 15

16 Basic Electricity and Electronics Module One Quiz Key 1. Which device opposes current? a. Resistor b. Capacitor c. Inductor d. Coil 2. Which of the following is a control device? a. Resistor b. Switch c. Fuse d. Ground 3. What is the most common material a resistor is made from? a. Silicon b. Metal film c. Carbon d. Ceramics 4. Which of the following is the symbol for current? a. A b. V c. Ω d. I 5. How much resistance does an insulator have? a. Zero b. Some c. A lot d. Infinite 6. Different elements always have different numbers of? a. Protons b. Neutrons c. Atoms d. Atomic shells Copyright Texas Education Agency, All rights reserved. 16

17 7. A volt is a/an: a. Potential difference between two points b. Unit of charge on an electron c. Rate of flow of charge d. Opposition to current flow 8. How many forms of Ohm s Law are there? a. One b. Two c. Three d. Four 9. Energy is: a. The fundamental ability to do work b. The rate at which energy is used c. The amount when one joule is used in one second d. The maximum amount of power dissipated without damage 10. A KW-Hr is a unit of: a. Energy b. Power c. Heat d. Voltage times current 11. An electrical load is: a. Any weight being carried b. The amount of horsepower in a circuit c. Any resistive element connected to a power supply d. Taking more than four classes a semester 12. Which of the following is a unit of power? a. Joule b. Joule per second c. Joule-second d. Volt-ohm Copyright Texas Education Agency, All rights reserved. 17

18 13. When the voltage across a resister is doubled, the current will: a. Triple b. Halve c. Double d. Not change 14. When the resistance in a circuit is doubled, the current will: a. Triple b. Halve c. Double d. Not change 15. Sound is the movement of: a. Air molecules b. Electrons c. Protons d. Electricity 16. A speaker acts similar to a: a. Generator b. Motor c. Transistor d. Battery 17. What performs the work in an electric circuit? a. Heat b. Voltage c. A resistor d. Current 18. What is the definition of current? a. The movement of electrons b. Force created by the buildup of charge c. Force times distance d. A twisting or rotary force 19. What is the definition of voltage? a. The movement of electrons b. Force created by the buildup of charge c. Force times distance d. A twisting or rotary force Copyright Texas Education Agency, All rights reserved. 18

19 20. What is resistance? a. The interaction of two magnetic fields b. Conversion of mechanical energy into electrical energy c. An imbalance between electrons and protons d. The opposition to current flow 21. What is the formula for Ohm s Law? a. P = V I b. I = V / R c. F = M A d. I = V 2 R 22. CD data represents: a. Signal frequency as a binary code b. Signal amplitude as a binary code c. Cosine transform coefficients d. Data reduction through elimination of masked signals 23. What is the sample rate of CD audio? a. 20,000 samples/second b. 128 Kbytes per second c. 44,100 samples per second d. 32 bits per second 24. The unit of resistance is the: a. Coulomb b. Joule c. Ampere d. Ohm 25. The unit of electrical charge is the: a. Coulomb b. Joule c. Ampere d. Ohm Copyright Texas Education Agency, All rights reserved. 19

20 26. A circuit has a 12 V power supply and a 1 kω resistor. What is the current? I = V/R = 12V divided by 1000Ω=.012 A or 12 ma 27. A circuit has a 42 kω resistor and 8 ma of current. What is the voltage? V = I X R =.008 A X 42,000Ω = 336 V 28. A circuit has 520 milli amps of current and 240 volts. What is the resistance? R = V/I = 240V divided by.52a = 461.5Ω 29. List some of the reasons electricity is so useful. A good power source Easy to create Easy to control Efficient to transmit Easy to measure Makes everything work our way of life depends on it Copyright Texas Education Agency, All rights reserved. 20

21 30. A circuit has 470 kω and 16 V. What is the current? I = V/R = 16V divided by 470,000Ω = A = 34 μa 31. I = 145 ma, R = 10 MΩ. V =? V = I x R =.145 A X 10,000,000Ω = 1.45 MV 32. In the following circuit calculate current and voltage drops. R 1 = 2 KΩ 12V R2 = 4 KΩ IT = 2 ma V1 = 4V V2 = 8V Copyright Texas Education Agency, All rights reserved. 21

22 33. In the following circuit, calculate total current and total resistance. 18V R1 = 2kΩ R2 = 4kΩ IT = 13.5 ma RT = 1333Ω 34. In the following circuit, what is R 1? R 1 R1 = 8 kω 12V I = 1 ma R2 = 4 KΩ 35. A power supply consumes 320 mw in order to supply 288 mw to the load. What is the efficiency? Eff = power out divided by power in = 288/320 =.9 = 90% 36. What is R 2 in the following circuit? I T = 12 ma 18V R1 = 2kΩ R2 =? R2 = 6 kω Copyright Texas Education Agency, All rights reserved. 22

23 Basic Electricity and Electronics Module One Problem Worksheet 1. A circuit has a 12 V power supply and a 1 kω resistor. What is the current? 2. A circuit has a 42 kω resistor and 8 ma of current. What is the voltage? 3. A circuit has 520 milli amps of current and 240 volts. What is the resistance? 4. A circuit has 470 kω and 16 V. What is the current? 5. I = 145 ma, R = 10 MΩ. V =? 6. In the following circuit calculate current and voltage drops. R 1 = 2 KΩ 12V R2 = 4 KΩ Copyright Texas Education Agency, All rights reserved. 23

24 7. In the following circuit, calculate total current and total resistance. 18V R1 = 2kΩ R2 = 4kΩ 8. In the following circuit, what is R 1? R 1 12V I = 1 ma R2 = 4 KΩ 9. A power supply consumes 320 mw in order to supply 288 mw to the load. What is the efficiency? 10. What is R 2 in the following circuit? I T = 12 ma 18V R1 = 2kΩ R2 =? Copyright Texas Education Agency, All rights reserved. 24

25 Basic Electricity and Electronics Module One Problem Worksheet Key 1. A circuit has a 12 V power supply and a 1 kω resistor. What is the current? I = V/R = 12V divided by 1000Ω=.012 A or 12 ma 2. A circuit has a 42 kω resistor and 8 ma of current. What is the voltage? V = I X R =.008 A X 42,000Ω = 336 V 3. A circuit has 520 milli amps of current and 240 volts. What is the resistance? R = V/I = 240V divided by.52a = 461.5Ω 4. A circuit has 470 kω and 16 V. What is the current? I = V/R = 16V divided by 470,000Ω = A = 34 μa 5. I = 145 ma, R = 10 MΩ. V =? V = I x R =.145 A X 10,000,000Ω = 1.45 MV 12V 6. In the following circuit calculate current and voltage drops. R 1 = 2 KΩ R2 = 4 KΩ IT = 2 ma V1 = 4V V2 = 8V Copyright Texas Education Agency, All rights reserved. 25

26 7. In the following circuit, calculate total current and total resistance. 18V R1 = 2kΩ R2 = 4kΩ IT = 13.5 ma RT = 1333Ω 8. In the following circuit, what is R 1? R 1 R1 = 8 kω 12V I = 1 ma R2 = 4 KΩ 9. A power supply consumes 320 mw in order to supply 288 mw to the load. What is the efficiency? Eff = power out divided by power in = 288/320 =.9 = 90% 10. What is R 2 in the following circuit? I T = 12 ma 18V R1 = 2kΩ R2 =? R2 = 6 kω Copyright Texas Education Agency, All rights reserved. 26