2. a path along which electrons flow must have no breaks in the path to work 2 types: –closed (no breaks) –open (break, causes the device to shut off - switch) 1. electronic current

3. 2. 4 parts of a circuit energy source load wires switch

4. 3. energy source pushes the electric charges through a closed circuit battery- has a positive and a negative terminal, one side repels electrical charges and one attracts

5. 4. load the device the circuit delivers the energy to examples: light bulb, bell

6. 5. wires connect the energy source to the load often copper, because it is a good conductor, wrapped in plastic insulation to keep the current from flowing to other conductors

7. 6. switch opens and closes a circuit by bringing together or separating two pieces of metal

8. 7. potential difference the measure of how much energy is lost when electrons go through a load the work needed to move a charge from one point to another measured in volts

9. 8. voltage amount of potential difference higher the voltage, the more energy the electrons have measured by a voltmeter

10. 9. current the number of electrons per second that flow past a point in a circuit measured with an ammeter SI unit of measurement in the ampere or amp

11. 10. resistance the ability of the material to oppose the flow of electrons through it measured in ohms Ω thin wire= more resistance because there is less room for the electrons to travel longer wire= more resistance

12. 11. conductors materials that allow for free and easy movement of electrons metals are good conductors, especially copper, silver, and aluminum

13. 12. insulators materials that are NOT good at carrying current examples: rubber, wood, glass the charge gets stuck and doesn’t move throughout the material