About Electricity-TG

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EXPLOR ATION
About Electricity
Teacher Guide
Overview
Students will understand that electricity is the flow of charged particles. They will explore how
charged particles can be contained as static or stored charges.
Student Learning Objectives
Summarize how a static generator conducts electricity when it comes in contact with some
objects.
Explain how electrical energy is stored in a battery.
Student Worksheet
The student worksheet includes questions to focus the student and to check understanding,
instructions for how to use the Exploration independently, and a section for recording data. Students
will review questions before participating in the activity, and can respond to the questions either
during or after completion of the activity. The section for recording data includes a table in which to
describe outcomes of investigations.
Exploration Procedure
Explain that the purpose of this Exploration is to learn how static and stored charges produce
electricity. Follow either of the procedures below.
Student Performs Exploration
1. Tell students how much time they will have to complete the Exploration and the student
worksheet.
2. Explain how students should proceed:
Read the questions before starting the Exploration.
Follow the instructions on the worksheet to perform the Exploration.
Record results.
Respond to the questions in writing.
3. Explain that you will be available to help any students who need assistance.
4. Address any questions that the students might have.
5. Tell students to begin the Exploration.
6. When time is up, ask students to share their results.
7. Talk about the Discussion Questions.
Exploration: About Electricity
© 2008 Discovery Communications, LLC
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EXPLOR ATION
About Electricity
Teacher Guide
Teacher Performs Exploration
1. Display the questions from the student worksheet and ask students to tell you what they think
they will learn from the Exploration based on its questions. Highlight key words.
2. Read the Introduction and click the Continue button.
3. Click the type of charge to explore it.
4. Read the instruction text and follow the instructions to learn about the flow of particles .
5. Watch the animation, read the outcome explanations as they appear, and discuss. Where
appropriate, record findings in the Data table.
6. Click the Choose another charge button to choose another type of charge.
7. Discuss each of the questions with the class. Replay parts of the Exploration as necessary to
illustrate the answers.
8. Click the Close button to close the Exploration.
9. Talk about the Discussion Questions.
Optional: Use this Exploration as a small-group activity at a computer station. Assign it to students
who need specific reinforcement of the concept.
Questions
1. Why do the strands of a mop push each other away when they come in contact with a positively
charged object?
Answer: The mop has electrons and protons. When the mop is placed over a positively
charged object, the electrons on it are pulled away leaving behind only protons. Like charges
repel each other. So, the strands of the mop are pushed away from each other.
2. A static generator comes in contact with a metal spoon. Explain the movement of electrons.
Answer: The static generator will pull the electrons away from the metal spoon. Metal is a good
conductor. So, the electrons on the generator will jump towards the protons on the spoon in the
form of sparks.
3. How are electrons arranged in a battery? How do they flow when the battery is connected in a
circuit?
Answer: Chemical reactions that take place in a battery create and move the electrons toward
the negative terminal of the battery. When the battery is connected in a circuit, electrons flow
from the negative terminal to the positive terminal of the battery.
Discussion Questions
Can you think of an example of electrically charged particles moving in nature?
Possible answer: Lightning. The negatively charged particles in the cloud move toward the
positively charged ground. This flow can be seen in the form of lightning.
Exploration: About Electricity
© 2008 Discovery Communications, LLC
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EXPLOR ATION
About Electricity
Teacher Guide
Why doesn’t the power in a battery last forever?
Possible answer: Electrons will no longer be stored when the chemicals in the battery are done
reacting. After that, there will be no more electrons to flow from the negative end to the positive end.
Then it is considered a ‘dead’ battery.
Exploration: About Electricity
© 2008 Discovery Communications, LLC
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