Circuits and Switches
Unit Summary
Learning about simple electrical circuits gives students some basic knowledge about electricity. This knowledge will enable them to more easily understand the complex circuits inside a computer. Computer circuits follow the same principles even if the components are not visible to the naked eye. The online lessons with readings, video demonstrations, and activities introduce students to:
- The basics of electricity
- Simple electrical circuits
- Electrical flow
- Conductive and nonconductive materials
- Huge electrical circuits at a hydro-electric power plant
- Mechanical and nonmechanical switches (transistors)
- AC and DC current
Students will work online with electrical circuits like the one shown in the figure below.
Goals and Objectives
Students will:
- Understand that an electrical current in a wire is a flow of electrons
- Be able to construct a simple, working circuit
- Understand conductivity of solids and how conductivity can be tested
- Learn some of the terminology used in circuitry
- Become familiar with the process of assembling and testing a variety of simple electrical circuits
- Understand that an electrical current in a wire can be controlled (turned on and off) by a switch; the switch may be mechanical (with moving parts) or electronic (no moving parts)
- Observe the action of a transistor in a simple circuit
- Understand the construction of a transistor
Time to Complete Online Lessons: about 30 minutes
Preparation
- Read the background information.
- Review and prepare for supplemental lesson ideas and group activities.
- Organize materials and equipment:
Student computers with an active Internet connection
Copies of the student handouts that you plan to use
Printouts of the interactive whiteboard images (optional)
A working flashlight (optional)
Tokens (optional)
Masking tape, aluminum foil, batteries, LED, or flashlight lightbulb (optional—used in Handout: Fun With Circuits)
- Have students complete the online activities.
Throughout the unit, facilitate the development of new vocabulary introduced in this unit.
Encourage students to use the new terminology of circuits correctly in their discussions and written work. - Students who are not at the computer can work on supplemental lesson ideas and group activities
This handout helps students:
- Understand our dependence on electricity
- Differentiate between alternating current (AC) and direct current (DC)
- Compare how electric current and water are delivered to our homes
This handout explains in text and diagrams how transistors work.
Fun With Circuits
This handout gives instructions on how to build a lightbulb circuit with:
- Aluminum foil
- Masking tape
- Flashlight-type lightbulb or LED
- 9-volt battery or C-cell batteries
Introduction to Computers
This unit provides a short history of the computer, introduces the four major components of a computer, and compares computer "brains" with the human brain.
Circuits and Switches
This unit teaches students about electricity, electric circuits, and the difference between mechanical and nonmechanical (transistors) switches.
Digital Information
This unit explores the differences between the decimal and binary number systems and how the information is represented and processed using binary code.
Microprocessors
This unit investigates how microprocessors process information, demonstrates the size and the complexity of their circuitry, and explains how they are manufactured.
The Internet
This unit defines the Internet, then explains the World Wide Web, hypertext, URLs, packets, bandwidth, connection choices, search engines, and the need to critically evaluate the quality of the information found on the Web.
Technology and Society
This unit discusses the impact technological advances have on people's lives, with examples from the past and current day. Several readings provide insights on ways the digital age is already affecting our lives, the accelerating rate of change, and what we might expect to see in the near future.