Electricity

Purpose:
To investigate charges and how they behave.

Location
HS Makerspace

Whole-Group Mini-Lesson
(HS teacher addresses whole group with laptop & smartboard/projector.) Where in your life have you experienced static electricity? What are the two kinds of charge? All things are composed of charges, but most objects are neutral Visual of object with equal numbers of + and - charge What do the charges look like in a charged object? The subject of our investigation: how do objects get charged?
 * SCox's Electricity Simulation Outline

Materials:
Tissue paper Green Vinyl Strips Clear Acetate Strips Comb Cotton cloth Wool cloth Wood pencil Plastic bag (cloth is stored in a plastic bag

Static Activity Part 1
1. Use the comb to comb your hair several times. Then bring the comb near your hair, what do you observe?

2. Would you guess that the hair and comb have the same charge or opposite charges?

3. Tear the tissue paper in small pieces and put the pieces on the table. Comb your hair several times again, and then slowly lower the comb over the pieces of tissue paper. What do you observe?

4. Use the ruler to measure how close the comb needs to be to the bits of paper before they react. Record your result and units here: ___

5. Now run your hand over the surface of the comb and try lowering the comb over the paper again. What do you observe?

6. What do you think running your hand over the comb did to the charges?

Static Activity Part 2
1. For each pair of things in the table, rub them together, and measure how close they need to be to the bits of paper before they react. Record your measurements and units in the table.


 * - || Green Vinyl || Clear Acetate || Wood Pencil ||
 * Cotton Cloth || - || - || - ||
 * Wool Cloth || - || - || - ||
 * Plastic Bag || - || - || - ||

2. Which pair created the strongest charge?

3. Which pair created the weakest charge?

Small Group Discussion and Follow Up
How do objects get charged?

How are neutral objects different from charged objects?

What are some ways that objects lose their charge?

Large Group Followup
(HS teacher addresses whole group with laptop & smartboard/projector, and Van de Graaff Generator) Discuss as a whole group the difference between neutral objects, which have equal numbers of charges, and charged objects which have unequal numbers of charges. Rubbing two things together can sometimes make this happen – which we can demonstrate up on the screen with the PhET Balloons & Static Electricity simulation. The Van de Graaff Generator can also produce this effect in a very dramatic way. Why does someone’s hair stand up when they touch it? What do you feel when you are being charged up? What do you feel when the charges move? What is the difference between the Van de Graaff and a battery?

Alternate Followup (used by SCox, 1/2011)
Demonstrate Van de Graff Generator Note: I did not use student volunteers, to avoid health/safety concerns with students I don't know--SCox.
 * with blue spark (teacher demonstrates);
 * with pompom;
 * with stacked aluminum pie plates.

Play [|Electrical Field Hockey] (Click play NOT download... Then click on the jnlp file.)

PA State Standards in Science and Technology – Grade 4
3.1.3.C Illustrate patterns that regularly occur and reoccur in nature.

3.1.4.A Know that natural and human-made objects are made up of parts.

3.2.4.B Describe objects in the world using the five senses.

3.2.4.C Recognize and use the elements of scientific inquiry to solve problems.

3.4.4.A Recognize basic concepts about the structure and properties of matter.

3.4.4.C Observe and describe different types of force and motion.