Editor selections by Topic and Unit

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## AP/Calculus-Based Physics:"Static" Electricity Units

Characteristics of "static" electricity include: 1) The number of of positive and negative electric charges within a material may not be equal, 2) voltage is high and current is low, 3) electrical forces (attraction and repulsion) can reach  across great distances, and 4) electric fields (as opposed to magnetic fields) become very important. (Electric fields are also called "electrostatic fields" or "e-fields." Units are not listed in a prescribed order.

#### Activities:

Help your students build a conceptual framework with this comprehensive set of simulations and videos that model electrostatic processes. Each visualization is supported with a rich collection of related lecture notes and homework questions, all available for free. Highly recommended.

Item Type: Digital Collection
Level: High School Physics

#### References and Collections:

This website from the University of Rochester offers 20+ demos designed to promote understanding of electrostatic processes. Build a leaf electroscope, a "dissectible" capicitor, a moving charge sensor, a piezoelectric sparker, and more.

Item Type: Classroom Demonstrations
Level: High School

This free online textbook was created by a veteran professor who blends written materials from "lectures that worked" with calculus-based problems and solutions.  The first two chapters deal with electrostatic phenomena.

Item Type: Digital Textbook

This unique resource integrates the scientific work of Ben Franklin with lab guides for replicating historic experiments in secondary classrooms. This introductory section describes the history of Franklin's work, and provides details of the equipment that will be used for the entire unit.

Item Type: Lab Experiments

#### Content Support For Teachers:

Common misconceptions about the topic of electrostatics are fully explored in this resource for both teachers and learners.  The author debunks more than a dozen myths as he offers comprehensive explanations of related phenomena.

Item Type: Reference Material

#### Student Tutorials:

What happens when a charged object is brought near a neutral conducting object? This animation will help your students visualize the process of induction. It was developed by the author of The Physics Classroom tutorials for high school physics.

Item Type: Interactive Tutorial
Level: High School Physics

This tutorial/animation goes into greater depth to explain and illustrate the process of induction.

Item Type: Interactive Tutorial
Level: High School Physics

#### Assessment:

This is a teacher-made electrostatic quiz, not meant to be fully definitive, but as an example. It contains 29 questions in multiple choice and true/false format. Answers are provided.

Item Type: Online Quiz
Level: High School

### Electric Field (14)

#### Lesson Plans:

Looking for a truly interactive lesson on electric field? This package was developed by an award-winning high school teacher to accompany the PhET simulation Electric Field Hockey. Students place electric charges on a simulated ice field, then use their understanding of charge interaction to guide a hockey puck into a goal. The lesson integrates the game with free-body diagrams and vector addition.

Item Type: Simulation-Based Lesson
Level: High School Physics
Duration: 1-2 Class Periods

#### Activities:

In this game-like environment, students place positive and negative charges on a simulated ice field.  Getting the puck into the goal can be easy or complicated, depending upon the charge interaction. Editor's Note: See "Lesson Plans" above for clicker questions and a student guide developed specifically to accompany this simulation.

Item Type: Interactive Simulation

We can't see an electric field. It helps students to have a pictorial tool to visualize it as a region of space. This simulation lets them explore both the vector field concept and the field line model. Click anywhere within the field and a field line is automatically drawn. Color-coded vectors surround each charge to show the strength of field. Sign can be changed to view both attraction and repulsion.

Item Type: Interactive Simulation

Visualizing electric field lines helps the student reinforce and comprehend the rules behind them. With one click, you can toggle between positive and negative charges, observing how this changes the direction of the field lines. Magnitude of charge can also be adjusted.

Item Type: Interactive Simulation
Level: High School Physics
Duration: 30 minutes

How is electric field created and how does it come to fill up space? This animation from MIT's TEAL Physics Project starts with two opposite point charges being separated to form a classic electric dipole field configuration. It will help students see that electric fields do not appear instantly in space when there is unbalanced charge. They propagate outward from a source in a predictable way.

Item Type: Interactive Simulation
Level: High School Physics

This 3D Shockwave simulation lets students explore how a dipole pattern arises as they move an "observation point" around two equal and opposite charges. By allowing them to see the field from a variety of reference points, they can visualize how each charge contributes to the resultant field.

Item Type: Interactive Simulation
Level: High School Physics

In this Java-based game, students use their understanding of charge interaction to "steer" a moving charge around a maze containing two fixed charges. By observing the changing field lines as they move the charge, students can devise a strategy to guide the particle to the exit. Editor's Note: We recommend the two animations directly above before introducing this activity.

Item Type: Interactive Simulation
Level: High School Physics

An outstanding, yet simple, simulation to help students visualize electric force as a vector with magnitude and direction. It features two particles with opposite charge. Change the position and magnitude of either charge and watch the electric field respond. The field can be viewed as "grass seeds", electric potential lines, or vector field.

Item Type: Interactive Simulation
Level: High School Physics

Understanding electric field can be easier if students start with a 1-D representation. This excellent simulation models the electric field at various points along a line. For a very simple version, use only one test charge and one charged particle. For a somewhat more challenging activity, add a second charged particle. Also contains a student worksheet specifically for use with this simulation.

Item Type: Computer Model
Level: High School Physics

#### References and Collections:

ESA is devoted to advancing communication among professionals in the field of electrostatics. ESA sponsors annual meetings, a free bi-monthly newsletter, and Conference Proceedings. If you're looking for cutting-edge applications of electrostatics concepts, this is your website.

Item Type: Reference Material
Level: High School Physics

#### Content Support For Teachers:

In this free resource, topics are connected in a well-organized concept map.  One click takes the teacher from electric field to related topics such as Gauss' Law, capacitance, and calculations related to force and field potential.

Item Type: Concept Map
Level: High School Physics

This educator's guide provides a conceptual explanation of electric field. It is framed as a side-by-side comparison of electrostatics and gravity, a solid analogy for understanding how charge interaction is described and quantified in physics.

Item Type: Content Support

#### Student Tutorials:

This chapter in an online educators' guide is devoted to a conceptual exploration of electric field.  It is framed as a side-by-side comparison of electrostatics and gravity, which helps beginners gain understanding of how charge interaction is described and calculated in physics.

Item Type: Student Tutorial
Level: High School Physics
Duration: 30 minutes

#### Assessment:

This is a multiple choice traditional online quiz (with hints) for electric fields.

Item Type: Online Quiz
Level: High School

### Electric Force (9)

#### Activities:

Inverse relationships are common in nature. In electrostatics, the electrical force between 2 charged objects is inversely related to the distance that separates them. This interactive tutorial from The Physics Classroom is the best we've found on the web for exploring and applying the inverse square law to electrostatics forces.

Item Type: Interactive Tutorial

In this Java-based game, students use their understanding of charge interaction to "steer" a moving charge around a maze containing two fixed charges. By observing the changing field lines as they move the charge, students can devise a strategy to guide the particle to the exit. Editor's Note: We recommend the two animations directly above before introducing this activity.

Item Type: Interactive Simulation
Level: High School Physics

An outstanding, yet simple, simulation to help students visualize electric force as a vector with magnitude and direction. It features two particles with opposite charge. Change the position and magnitude of either charge and watch the electric field respond. The field can be viewed as "grass seeds", electric potential lines, or vector field.

Item Type: Interactive Simulation

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.

Item Type: Interactive Simulation

Many students have difficulty understanding the interactions that cause an electric force between charges. It helps if they begin their investigation with a very simple 1-D representation of the electric force that one particle exerts on another. The user sets the amount of charge so that the particles can either attract or repel; then vector arrows appear to show the amount of force on each particle. One particle can be moved left or right along the line to see the effect of distance on the force. With one click, students can see a graph of the electric force as a function of position.

Item Type: Interactive Simulation
Level: High School

#### References and Collections:

This is a wonderful collection of materials on the scientific works of Benjamin Franklin, integrating historical background with descriptions of the actual lab experiments. The lab guides explain how to set up identical (or very similar) experiments in the classroom and provides video how-to's for several lessons.

Item Type: Digital Collection

#### Content Support For Teachers:

In this free resource, topics are connected in a well-organized concept map.  This section gives a concise, yet thorough explanation of Coulomb's Law and how it it is used to determine the electric force between charges.

Item Type: Content Support
Level: High School Physics

#### Student Tutorials:

This interactive tutorial, part of The Physics Classroom, does a first-rate job of explaining the concepts underlying Coulomb's Law.

Item Type: Interactive Tutorial
Level: High School
Duration: 30 minutes

This short biography on Charles-Augustin de Coulomb (1736-1806) gives background on the pioneer's work, which resulted in the fundamental physics law named after him. Coulomb's Law states: the electric force between charged objects inversely depends upon the distance between the objects. This tutorial helps students understand this relationship.

Item Type: Historical Background

### Capacitors and their Effect on Electricity (3)

#### Activities:

This is one of the best simulations we've seen to illustrate what happens at the particle level inside the two plates of a parallel capacitor. Students can set the number and magnitude of charges within each capacitor, then watch the charges distribute themselves along the outer edges of their enclosures. A great visualization of the Coulomb force in action.

Item Type: Interactive Simulation

#### Content Support For Teachers:

In this free resource, topics are connected in a well-organized concept map.  One click takes the teacher from capacitors to related topics such as dielectrics, storage devices, and impedance.

Item Type: Concept Map
Level: High School Physics

This resource blends text with interactive java simulations to provide an excellent overview of the topic of capacitance.  It includes descriptions of how electric capacitors work and introduces simple calculations.

Item Type: Interactive Tutorial
Level: High School

### Electric Charge (7)

#### Lesson Plans:

Looking for a truly interactive lesson on electric field? This package was developed by an award-winning high school teacher to accompany the PhET simulation Electric Field Hockey. Students place electric charges on a simulated ice field, then use their understanding of charge interaction to guide a hockey puck into a goal. The lesson integrates the game with free-body diagrams and vector addition.

Item Type: Simulation-Based Lesson

#### Activities:

In this game-like environment, students  place positive and negative charges on a simulated ice field.  Getting the puck into the goal can be easy or complicated, depending upon the charge interaction. See "Lesson Plans" above for a great set of teacher-created materials that supplement this simulation -- student guide, clicker questions, and more.

Item Type: Interactive Simulation

This simple and effective Quicktime video shows a model of a negatively-charged particle being pulled in by the positively-charged sphere of a van de Graaff generator.  Although the particle is not touching the generator, they are in direct contact with a medium existing between them. We recommend viewing this item in stepped motion.

Item Type: Animation
Level: High School Physics

This Quicktime video accompanies the item directly above. In this model, a positively-charged particle is shown being repelled by the positively-charged sphere of the van de Graaff generator. Both videos promote understanding of the Coulomb force by showing the electric field existing between the charges.

Item Type: Animation
Level: High School Physics

An outstanding, yet simple, simulation to help students visualize electric force as a vector with magnitude and direction. It features two particles with opposite charge. Change the position and magnitude of either charge and watch the electric field respond. The field can be viewed as "grass seeds", electric potential lines, or vector field.

Item Type: Interactive Simulation

#### References and Collections:

The Van de Graaff generator, invented in 1929, is an example of a nearly ideal current source, as it can supply the same small current at almost any electric potential. This site offers information needed to understand the operation and maintenance of Van de Graaff generators.  The author includes helpful hints for classroom demonstrations.

Item Type: Reference Material

#### Student Tutorials:

This multimedia resource from NOVA explores the electrostatic forces that cause lightning. It features a nine-minute Flash video, an interactive tutorial on varieties of lightning, an "Ask the Expert" question-answer session, and background information for teachers.

Item Type: Multimedia Package
Duration: One Class Period

### Franklin and Electrostatics (6)

#### Activities:

Franklin's second letter about transfer of electrical fluid in Leyden jars is accompanied by descriptions for setting up the experiments in a classroom.

Item Type: Annotated Historical Lab
Duration: One class period

This item highlights Benjamin Franklin's historic first letter about points and Leyden jar experiments, describing how to set up the labs in the classroom.

Item Type: Annotated Historical Lab
Duration: One Class Period

This item integrates a third historic Franklin letter with directions on how to construct a flat-plate capacitor and an electrostatic motor.

Item Type: Annotated Historical Lab
Duration: One Class Period

Franklin's theory of atmospheric electrification is highlighted, with diagrams and annotations to enhance student understanding.

Item Type: Annotated Historical Lab
Duration: One Class Period

This item highlights Ben Franklin's proposal to experiment with the lightning rod.  Historic text is augmented with detailed diagrams, photos, and editorial explanations.

Item Type: Annotated Historical Lab
Duration: One Class Period

#### References and Collections:

This is the introductory segment of materials by author Robert Morse on the scientific works of Benjamin Franklin. It integrates historical background and primary source documents alongside lesson plans for setting up identical (or very similar) experiments in the classroom. It includes a template for building a generator, plus video how-to's for several lessons.

Item Type: Digital Collection

### Electrostatic Induction (2)

#### Activities:

This Java simulation from MIT is one of our top choices to model the process of electrostatic induction. It breaks the process down into steps: charge separation within the conductor, grounding of charge, and ungrounding. It gives students an especially rich experience, as they can observe the changing electric field as "grass seeds", electric potential lines, or in a 3D view.

Item Type: Interactive Simulation
Level: High School
Duration: 20-30 minutes

#### Student Tutorials:

Electrostatic induction is a redistribution of electrical charge in an object. Induction is one way to charge an object (friction or rubbing is another way). The induction process can be confusing to students, and this Physics Classroom tutorial does a terrific job of making it clear. Includes a Q & A set to self-test understanding.

Item Type: Interactive Tutorial
Level: High School Physics
Duration: 1-2 Class Periods