Editor selections by Topic and Unit

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## Physics First:Electricity and Electrical Energy Units

Electricity is a natural phenomenon that can be both invisible AND visible, both matter and energy, a type of wave made of protons or a force that cannot be seen. It can move at the speed of light... yet it vibrates in a cord without flowing at all. It can be weightless, or have a small weight. Flowing in a light bulb filament, it transforms into light, but is not used up. It can  be stored in batteries. "Electricity" is not only a class of phenomena; it's a type of event.

### A Model for Electricity (2)

#### Activities:

This high-quality simulation, now in HTML5, can be easily adapted for both middle school and high school. Students build a virtual DC circuit by clicking & dragging  wires, batteries, switches, and resistors. This particular resource has received excellent reviews in extensive field testing, especially when done in conjunction with a hands-on lab.

Item Type: Interactive Simulation

#### Content Support For Teachers:

It may be easier to understand about electricity if we think of electric charge as a sort of a fluid, like water, as scientists did for over 200 years. This tutorial by David Stern introduces Ohm's Law and electric field concepts through this analogy.

Item Type: Online Tutorial
Duration: One Class Period

### Electrical Charge (2)

#### Lesson Plans:

This lesson plan features the neon bulb, an object that can be lighted either by electric current or by static electricity.  Accompanied by detailed background information, this lesson promotes conceptual understanding of  electron transfer.

Item Type: Lesson Plan
Duration: One Class Period

#### References and Collections:

This collection of 50+ interactive java tutorials would be an excellent choice to connect physics to real-world applications.  Designed by well-respected authors, the topics range from electric and magnetic fields to primers on capacitance, resistance, Ohm's Law, and electromagnetic induction.  Included are simulations on how things work, such as vacuum tube diodes, cathode rays,  capacitors, AC/DC generators, hard drives, pulsed magnets, and speakers.

Item Type: Interactive Tutorials

### Moving Charges and Electric Circuits (9)

#### Lesson Plans:

If you like the PhET Circuit simulator (and who doesn't?) you'll appreciate this set of inquiry-based activities developed especially to accompany the sim. Designed by PhET Gold-Star winner Trish Loeblein, the activities explore basic properties of electric circuits, resistors in series and parallel circuits, and more. Bonus: includes clicker questions. Note: Only registered PhET users can access teacher-created materials, but registration is free and easy.

Item Type: Activities
Duration: 2-3 Class Periods

Don't have time to do three lessons with the PhET Circuit Simulator? This lesson plan, specifically designed for use with the simulation, takes one day in computer lab and one follow-up day. We highly recommend it as a way to let your students explore circuits, learn from mistakes, and be better prepared to participate in the hands-on circuit lab.

Item Type: Lesson Plan
Duration: One Class Period

This module asks students to apply knowledge of electric circuits in designing a system where one switch can turn on multiple lights. Students work in teams to predict the difference between the two circuit designs, and then build examples of the two systems using wires, bulbs, and batteries. Editor's Note: We recommend teaming this lab with the PhET DC Circuit Simulator, found in "Activities" below.

Item Type: Lab Activity
Duration: Two Class Periods

#### Activities:

This high-quality simulation, recently rewritten to HTML5, is a good choice for introducing DC circuits. Students click and drag wires, batteries, switches, and resistors to explore factors that affect current, voltage, and resistance. The sim can be adapted for beginners or more advanced learners. This particular simulation has received excellent reviews in extensive field testing, especially when done in conjunction with a hands-on lab. See Lesson Plans above for recommended lessons developed by a high school teacher specifically for use with this simulation.

Item Type: Interactive Simulation
Duration: One Class Period

For the novice with little prior experience in circuit construction, this item offers well-organized step-by-step directions for building a simple circuit using a power pack system constructed by students. Also included is a tutorial on basic vocabularies needed to understand electricity.

Item Type: Activities
Duration: One Class Period

A collection of 8 experiments designed to introduce important concepts of electricity to beginning students. Each lab is accompanied by instructional tips to help students form a solid basis for a future study of resistance, Ohm's Law, and potential difference.

Item Type: Lab Experiments

#### References and Collections:

Want to go beyond your traditional textbook in a unit on electric circuits? This free web-based textbook offers solid content support for both learners and teachers. The text is student-friendly, blended with many diagrams and photos. Each section is further supplemented with suggested labs and activities. Did we mention, it's free?

Item Type: Open Source Textbook

#### Student Tutorials:

Good jumping-off point for students with little background in electricity. This is Chapter 1 of free online textbook, All About Circuits. With entertaining language and detailed diagrams, the author helps students form accurate concepts of electron transfer and charge interaction so they can successfully apply the knowledge in a lab.

Item Type: Online Tutorial

#### Assessment:

This is an exemplary set of 50+ short assessments on the basics of electricity and electric circuits. They offer teachers flexibility: 1) students can go online to interactively answer questions and see correct responses, 2) Students can work in small groups to discuss strategies before looking at answers, or 3) Teachers can print the worksheets with answers hidden. Most of the questions require analytical reasoning and will help teachers gauge whether students are getting the big picture.

Item Type: Open Source Worksheets

### Resistance and Ohm's Law (2)

#### Activities:

Robust activity features six molecular models to explore relationships among voltage, current, and resistance. This well-sequenced resource will help learners understand how current is different from voltage and visualize how electron movement is related to conductivity. More advanced students can explore a hydrogen fuel cell model, an incandescent light bulb filament, and electromotive force.

Item Type: Interactive Model
Duration: Two Class Periods

In this activity from the PTRA manual "Role of the Laboratory in Teaching Introductory Physics", students set up their first circuit using meters and specially made resistors in heat sink boxes, which do not require alligator clips and don't burn hands.

Item Type: Laboratory
Duration: 1-2 Class Periods

### Applying Concepts of Electricity (6)

#### Lesson Plans:

A very effective lab for reinforcing the importance of circuit continuity. A lamp is connected to a battery with jumper wires. After measuring normal voltages in a functioning circuit, students break the circuit at each of the four connecting points, then measure again. Editor's Note: For additional practice in measuring voltage, see "Voltmeter Usage" activity below.

A collection of 8 experiments designed to introduce important concepts of electricity to beginning students. Each lab is accompanied by instructional tips to help students form a solid basis for a future study of resistance, Ohm's Law, and potential difference.

#### Activities:

A very good introduction to the multimeter, an electronic instrument that measures voltage, current, and resistance. It will help students become comfortable using either a digital or analog multimeter with batteries, an LED, and a simple "hobby" motor.

This is a companion lab to the resource directly above, "Voltmeter Usage". It helps students get practice in using the ammeter function of a multimeter to measure current -- the rate of electron flow in a circuit. Detailed instructions and photos make set-up easy.

A set of 5 creative labs for constructing various types of primary battery cells, all appropriate for use in the high school science classroom. Two of the labs can be performed without corrosive chemicals: the voltaic pile and the lemon cell. The remaining 3 labs use either sulfuric acid or zinc chloride. Each lab contains detailed information on safety precautions and classroom set-up.

#### Assessment:

This is an exemplary set of 50+ short assessments on the basics of electricity and electric circuits. They offer teachers flexibility: 1) students can go online to interactively answer questions and see correct responses, 2) Students can work in small groups to discuss strategies before looking at answers, or 3) Teachers can print the worksheets with answers hidden. Most of the questions require analytical reasoning and will help teachers gauge whether students are getting the big picture.

### Electricity: A Historical Perspective (9)

#### Lesson Plans:

In this lab activity for Grades 5-9, students work in teams to construct a simple telegraph using a battery, wires, and a bulb. By turning the switch on and off, learners "send" messages using International Morse Code. Students then repeat the process sending identical messages on cell phones. Which group can send intelligible messages most quickly?  Editor's Note: This lab activity does not mimic the actual design of the original Morse device, which used electric current to move an electromagnet attached to the key device. Its purpose is to give a simple introduction to signal communications.

Item Type: Lesson Plan
Duration: One Class Period

#### Activities:

In this Java simulation, your students play with a replication of Coulomb's historic torsion balance: a device used to measure electric force between charges. Coulomb's methodical measuring laid the foundation for Coulomb's Law, a fundamental principle of electricity and magnetism.

It sometimes helps students with concept formation if they can see how early scientists made momentous discoveries. In this tutorial, students play with a simulation of the voltaic pile device invented in 1800 by Volta -- commonly known as the world's first battery. Battery cells can still be assembled using this "recipe". SEE ITEM DIRECTLY BELOW for a lab to construct the voltaic pile device in the classroom.

If you'd like your students to replicate Volta's groundbreaking experiment with the voltaic pile device (the world's first battery), here is a lesson plan (scroll down to Page 2 of the document). They will construct their own voltaic pile batteries and get a better understanding of how electrochemical reactions work. No harsh chemicals or safety hazards.

#### References and Collections:

In this excellent set of 50+ short biographies, kids can read about the challenges of early inventors AND follow links to simulations of the devices they invented. For example, the Coulomb biography offers a simulation of the torsion balance; the Volta biography has a simulated voltaic pile battery.

A short biography of Charles-Augustin de Coulomb, whose historic work in the 18th century was essential to the development of electromagnetic theory. Read about his experiments with a torsion balance and how he discovered the mathematical relationship known as Coulomb's Law.

#### Student Tutorials:

In the 18th-century, Italian scientist Alessandro Volta proposed the theory that electrical current is generated by contact between different metals. His experimental work resulted in the "voltaic pile" battery, the first known source of sustainable electric current. For a simulation of the voltaic pile device, see "Activities" above.

This is a short biography of Charles Augustin de Coulomb, the 18th-century scientist whose experiments with a torsion balance gave rise to Coulomb's Law -- a fundamental principle of physics that defines the electrical force between two charged particles as a predictable mathematical relationship. For a simulation of Coulomb's torsion balance, see "Activities" above.

German physicist Georg Ohm was different, and his fellows at the time were not too supportive. This early giant in the field of electricity took a mathematical approach to electric current, at a time when his peers relied almost exclusively on lab experimentation. His perseverance resulted in Ohm's Law, which clarified the relationship between electrical current, resistance, and voltage. This is his biography.