1 / 20

Circuits and Switches

Circuits and Switches. Brooke Baker Amy Fisher Rebecca Payton. Information adapted from: Intel's Explore the Curriculum. What is Electricity? . Electron- Negatively charged particle in an atom Electrons can jump from atom to atom

damali
Download Presentation

Circuits and Switches

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Circuits and Switches Brooke Baker Amy Fisher Rebecca Payton Information adapted from: Intel's Explore the Curriculum

  2. What is Electricity? • Electron- Negatively charged particle in an atom • Electrons can jump from atom to atom • There must be an imbalance for electrons to jump and there must be more at one end than the other • Electric Current- When electrons flow from the negative to the positive to correct imbalance

  3. Plumbed For Electricity • Household electricity is very similar to household plumbing!!! * A supply of water somewhere * A pipe to carry the water * A pressure difference between the water supply and your faucet * A faucet to turn the water on and off * A power plant to supply moving electrons * Wire to conduct the moving electrons * More moving electrons at the power plant than in your lamp * A switch to turn the current on and off Each have a supply, place to move, a difference, and an on/off!!

  4. Is Your House Plumbed for Electricity? • What examples of electricity can you think of within your home??

  5. Big Circuits • There are lots of power circuits! • Power Source- Dam-Generates a huge flow of electrons that can run for thousands of miles. • Conducting Path- Covers 14 western states and one line goes all the way to Canada and another to the Mexican boarder. • Transmission lines take electricity long distances to power plants. • Distribution lines take power to schools, homes, etc.

  6. The Flashlight • Simple Circuits have four parts: Power Source, Conducting Path, Switch and Load • A flashlight is a simple circuit

  7. Flash Light Activity

  8. Flash Light Activity Answers Switch Conducting Path Electrical Load Power Source

  9. Building a Lightbulb Circuit Guiding Question: • Do you think that reversing the wires will make a difference? Why or why not? Will the lightbulb still light up with the wires switched?

  10. Answer

  11. Will it or Won’t it? (solids) “Current” is the flow of electrons through a material. But what is “material”? In electric circuits, there are basically two kinds of material. • A “conductor” creates a pathway for electrons to move. • An “insulator” (or nonconductor) prevents the flow of electrons.

  12. Practice with “Will it or Won’t It!” • Practice using materials as conductors by clicking the picture below.

  13. Resistance video Resistance is the physical property of materials. • Metals have a low resistance (that’s why they’re used as electrical conductors). • Rubber, wood, and plastics have a high resistance, therefore, are not used as electrical conductors. Click picture for video

  14. Practice with “Will it or Won’t it?” (liquids) • Current doesn’t just flow through solids that are conductors, but also through liquid conductors as well. • Click on the picture below to practice with liquid conductors.

  15. Mechanical Switches • Allow you to turn things on and off. • Have many MOVING parts

  16. Activity 1- When will the light bulb turn on? • Switch A On and Switch B On • Switch A On and Switch B Off • Switch A Off and Switch B On • Switch A Off and Switch B Off • The answer is: 1 (Switch A On and Switch B On)

  17. NonmechanicalSwitches • Superfast switch with NO moving parts • Needs a semiconductor- a naturally poor conductor that could be easily modified to conduct electricity under certain conditions. • SILICON= best material for semiconductor and led to invention of the transistor- a switch with NO moving parts and uses electricity to turn itself on and off

  18. Activity 1- How do nonmechanicalswitches work? With ChargeWithout Charge Source Drain A Single N-type Transistor When a charge is applied to the gate terminal, electrons in the p—silicon are drawn to the space between the source and drain terminals and form an electron channel. Electrons now flow from the source to the drain. In this position, the transistor is on. Remove the charge from the gate terminal and the transistor returns to its off state.

  19. Activity 2- Why does the LED light up by itself but NOT with a transistor? Non-mechanical switch Non-mechanical without transistor with transistor? Answer: A transistor is a non-mechanical switch, but it needs something to turn it on. It needs a charge to its gate terminal to enable the flow of electrons through the transistor.

  20. Why do you think the gate terminal is called a “gate”? • Non Mechanical Switch with transistor and gate ANSWER: The gate terminal functions like a gate because it opens a path for electrons to flow when you apply charge. It closes the path when you take the charge away. This “gate” can open and close with no moving parts.

More Related