Electricity and Electrical Circuits

1. Electricity and Electrical Circuits A “Shocking” Force of Nature 2

2. Holding the Sun…

3. Electricity and Electrical Circuits Today’s Warm-up: • The Electric Pickle… aka “Frankenpickle”

4. Electricity / Electrical Circuits • Notes Outline Notes Notes Notes Notes Notes Notes Notes Notes Notes Notes Summary of the notes and information learned

5. Electricity and Electrical Circuits • Electrical Vocabulary • Electrical Symbols • Volts, Amps, Ohms • Ohm’s Law • Electrical Circuits • Series circuits • Parallel circuits • Home Wiring • Short Circuits

6. Electricity and Electrical Circuits Today’s Objectives: Review electricity basics Understand the vocabulary of electricity including circuit diagrams Electricity Computer Lab Activity Volts, Amps, Ohms Ohm’s Law Electrical Circuits Series circuits & Parallel circuits Home wiring & Short circuits Circuits Lab Activity

7. Electricity and Electrical Circuits • Electric energy is one of the most common and useful forms of energy available to us. • Electricity is the flow of electric current (positive or negative charges). That flow can accomplish work. • This energy is used to power most of the appliances/devices we depend on daily- alarm clock, TV, electric lights, microwave oven, LCD projector, etc…

8. Electricity and Electrical Circuits • Electricity flows in a circuit- a closed loop or path through which the charge travels • Opening or interrupting that closed loop (like w/a switch) stops the flow of electricity

9. Electricity and Electrical Circuits • Electric charge, like mass, is a fundamental property of matter and can be positive, negative, or neutral • Most matter is electrically neutral, but items can become “charged” by collecting excessive positive or negative charge • When these charges build-up but are not flowing… You get static electricity.

10. Electricity and Electrical Circuits

11. Electricity and Electrical Circuits - - - - - - Negative charges - - - - - - Positive charges +++ +++ +++

12. Electricity and Electrical Circuits

13. Circuit Diagrams • Many time when drawing electric circuits we use a shortcut method of symbols

14. Circuit Diagrams

15. Electric Circuits Lab

16. Circuit Diagrams Like water pressure in a hose Like water volume in a hose Like a restriction or kink in the hose

17. Electric Circuits BrainPop

18. Electrical Vocabulary • Ohms Law l

20. Electrical Vocabulary Ohms Law These variables are connected together in a relationship that is called Ohm’s Law- visually demonstrated at the following website: http://phet.colorado.edu/new/simulations/sims.php?sim=Ohms_Law

21. Electrical Vocabulary Ohms Law What is the current of a circuit that has a voltage of 1.5 V and a resistance of 3 ohms (Ω)? I = V/R I = (1.5 V)/(3 Ω) = .5 Amps • What is the current of a circuit that has a voltage of 3 V and a resistance of 3 ohms (Ω)? I = V/R I = (3 V)/(3 Ω) = 1 Amp • What is the resistance of a circuit that has a voltage of 4.5 V and a current of 1.5 Amps? R = V/I R = (4.5 V)/(1.5 Amps) = 3 Ohms (Ω)

22. Electrical Vocabulary Ohms Law What is the resistance of a circuit that has a voltage of 1.5 V and a current of .25 Amps? R = V/I R = (1.5 V)/(.25) = 6 Ohms (Ω) What is the voltage of a circuit that has a current of .5 Amps and a resistance of 6 Ohms (Ω)? V = I X R R = (.5 Amps) X (6 Ohms (Ω)) = 3 Volts What is the voltage of a circuit that has a current of .75 Amps and a resistance of 6 Ohms (Ω)? V =I X R R = (.75 Amps) X (6 Ohms (Ω)) = 4.5 Volts

23. Electrical Circuits • Electrical circuits can be created in two primary forms: • Series circuits have only one path; the flow of charge has only one place to go. • Parallel circuits have branching points and multiple paths for current to flow.

24. Electrical Circuits • In a series circuit the current can only take one path. All the current flows through every part of the circuit. • In a parallel circuit the current can take more than one path. Parallel circuits have at least one branch where the current can split up.

25. Electrical Circuits • Holiday lights are another good example of the difference between series and parallel circuits. Cheaper strands of lights are in series; higher quality lights are wired in parallel.

26. Electrical Circuits- House wiring • The electrical circuits in homes and buildings are parallel circuits. There are two great advantages of parallel circuits that make them a better choice than series circuits. • Each outlet has its own current path. This means one outlet can have something connected and turned on (with current flowing), while another outlet has nothing connected or something turned off (no current flowing). • Every outlet sees the same voltage because one side of each outlet is connected to the same wire. • Why would you not want to use series circuits in homes?

27. Electrical Circuits- House wiring

28. Electrical Circuits- Short Circuits • A short circuit is a circuit path with zero (or very low) resistance. • Short circuits are dangerous because they can allow huge amounts of current. (more current = more heat) • Too much current would melt the wire in an instant and possibly cause a fire. • Fuses or circuit breakers are protection from the high current of a short circuit. • Every electrical outlet in your house or apartment is connected to a circuit breaker that allows a maximum of 15 or 20 amps to flow. If something electrical breaks and causes a short circuit, the breaker will open before the current has time to cause a fire.

29. Electrical Circuits- Short Circuits OPEN CLOSED SHORT

30. Electricity and Electrical Circuits Electrical Circuits Lab Activity Work in same groups of two Recreate drawn circuits in real life

31. Electricity and Electrical Circuits Electrical Circuits and Ohm’s Law Homework Sheets Due by next class period READ THE FRONT FIRST!

32. Electricity / Electrical Circuits • Notes Outline Notes Notes Notes Notes Notes Notes Notes Notes Notes Notes Summary of the notes and information learned

33. Make it a great day Mustangs!