Electricity SOL 4.3 (Information used from

Currents and Circuits  A continuous flow of negative charges (electrons) is a current.  The pathway taken by an electric current is a circuit. Closed circuits allow the movement of electrical energy. Open circuits prevent the movement of electrical energy.

Circuits  Open Circuit  Lights off  Closed Circuit  Lights on

Series and Parallel Circuits  There is only one pathway for the current in a series circuit.  In a parallel circuit, there are two or more pathways for the current.

Conductors  Help electrical energy move better  Good conductors: metals and water

Insulators  Do not help electrical energy move through materials  Can be used to reduce heat produced by friction  Good insulators: rubber, plastic, wood

Static Electricity  Rubbing certain materials together can create static electricity. (rubbing your shoes repeatedly on carpet and then shocking your friend when you touch them!)  Lightning is the discharge of static electricity in the atmosphere.

Electrical Energy  Can be transformed into heat, light or mechanical energy  An electric current creates a magnetic field, and a moving magnetic field creates an electric current. This current can produce electrical energy.  Benjamin Franklin learned that lightning was a form of electricity.  Thomas Edison invented the light bulb.  Michael Faraday invented batteries.

Electromagnets  Created by a current flowing through a wire  Wrapping a wire around an iron nail and then connecting the ends with a battery is an example of a simple electromagnet. They are very useful because you can turn them on and off.

Quiz Time #1  Which will light a light bulb?  A. An open circuit  B. A closed circuit  C. Both A and B  D. Neither A nor B Correct Answer-B

Quiz Time #2  If you have a string of holiday lights on your tree and they go dark when one little bulb burns out, the string of lights is a...  A. Series Circuit  B. Parallel Circuit  C. Conductor  D. Insulator Correct Answer-A

Quiz Time #3  If you have a set of lights where one bulb burns out but the others remain lit, it is a...  A. Series circuit  B. Parallel circuit  C. Conductor  D. Insulator Correct Answer-B

Quiz Time #4  Electrical energy moves easily through materials that are good conductors. Which one of these is the best conductor?  A. Wood  B. Rubber  C. Cloth  D. Metal Correct Answer-D

Quiz Time #5  You are working on an experiment and your wires keep overheating and stopping your work. What insulator could you use to help solve this problem?  A. Rubber  B. Copper  C. Iron  D. Nickel Correct Answer-A

Quiz Time #6  This is a dry-cell battery. Who is credited for inventing batteries?  A. Benjamin Franklin  B. Franklin Roosevelt  C. Michael Faraday  D. Thomas Edison Correct Answer-C