1. Electricity and Circuits Electrical energy or electricity is produced by the movement and distribution of these charged particles 1

2. The Flow of Charges Electrons orbit the nucleus of an atom at different disturbances often referred to as levels. Each energy level contains a particular number of electrons at its maximum 2

3. The Flow of Charges Electrons in all energy levels are held tightly in place and are less likely to move to other levels * Electrons in the outermost energy level can jump from one atom to another quite easily 3

4. The Flow of Charges These jumps change the overall charge of the atoms Changes in the distribution of charges results in what is commonly called electricity 4

5. Electric Current Electric current is the flow of electric charges Electric current is measured in amperes or amps Electric charges will always flow from a region of higher potential energy to a region of lower potential energy 5

6. Electric Current The difference in potential energy between two locations is known as potential difference Potential difference results from difference in the electrical charges in two locations 6

7. Electric Current Potential difference is called voltage and is measured in units called volts 7

8. Electric Current A battery is a device that converts chemical energy into electricity In batteries, the potential energy difference is created by the positive and negative terminals 8

9. Circuits A circuit is a path through which electricity can flow Charges will flow in a circuit when there is potential difference 9

10. Circuits Most circuits have three parts: 1.An energy source 2.One or more loads 3.Conductors that connect the two 10

11. Circuits A circuit may also have a switch that can be open, which stops the flow of current, or closed which allows current to flow 11

12. Circuits Energy flows only through a circuit that is closed Opening a circuit stops the movement of charged particles that produces an electric current 12

13. Energy Source A circuit needs an energy source to push a charge through the circuit A battery creates a potential difference between its negative and positive terminals 13

14. Energy Source Electric charges are repelled by the negative terminal and attracted toward the positive terminal 14

15. Loads A load is a device in a circuit that operates using electrical energy Examples of loads are light bulbs, bells, radios, and motors 15

16. Conductors A conductor is a material that allows electrical energy to flow through it easily Wires drawn from metals are most often the conductors in circuit 16

17. Conductors Wires carry electrical current from the energy source to the load or loads that are part of the circuit 17

18. Resistors A resistor is an object added to a circuit that restricts the flow of electrical energy Resistors inhibit the flow of electric current by providing a voltage drop when current passes through them 18

19. Conductors Resistors can be used to produce a desired potential difference They limit current and cause some electric energy to be given off as heat 19

20. Switch A switch is a device that is used to control the flow of current through a circuit A switch works by separating (open) or bringing together (closed) two conductors attached to the circuit 20

21. Switch When the switch is open, the path that the electric charge can follow is broken so no electricity flows through the circuit When the switch is closed it creates a continuous path through which an electric charge can flow 21

22. Series Circuits Circuits can be set up in series or in parallel A series circuit is a circuit that provides only one possible path for the flow of current 22

23. Series Circuits In a series circuit, the loads are set up in a series, or line, that requires current to flow through one load before passing through the next 23

24. Series Circuits Electricity flows from the battery through each bulb, through the switch and then back to the battery Electricity in a series circuit has only one path to follow 24

25. Series Circuits A failure or break in any part of the circuit, such as a burned out bulb or an open switch, will stop the flow of electricity through the entire circuit All loads share the same energy source 25

26. Series Circuits This means that the current lowers as more loads are added to the circuit If these loads are bulbs, adding additional bulbs can cause the light given off by the bulbs to be dimmer 26

27. Parallel Circuit A parallel circuit offers more than one path for the flow of electricity An example of a parallel circuit that has two paths for electrical current Each load in a parallel circuit has its own closed circuit pathway to the energy source 27

28. Parallel Circuit Which means each load has its own path for electricity Because a parallel circuit provides more than one path for electricity, a failure in one part of the circuit will not affect another part of the circuit 28

29. Parallel Circuit If a bulb burns out in one path, current can continue to flow through the circuit by following another path The loads in a parallel circuit do not share current in the way that loads connected in series will share 29

30. Parallel Circuit Each load connected to a parallel circuit uses the full voltage of the energy source Adding more parallel loads to the circuit does not affect the current flowing through the other loads 30

31. Parallel Circuit The lights will not be dimmer as more lights are attached 31