1. Circuits Electric Current Series vs. Parallel

2. Let’s Review 0 What is electricity?

3. Let’s Review 0 What is electricity? 0 briefly defined as the flow of electric charge 0 the flow of electrical energy through conductive materials.

4. Let’s Review 0 What is electricity? 0 briefly defined as the flow of electric charge 0 the flow of electrical energy through conductive materials. 0 Electricity = Energy 0 Two types: Static and Dynamic 0 What is dynamic electricity?

5. Let’s Reviewish… 0 What is dynamic electricity? 0 Transfer of electrons from positive to negative points through a conductor. 0 ELECTRIC CURRENT

6. Let’s Reviewish… 0 What is the measurement for electric current?

7. Let’s Reviewish… 0 What is the measurement for electric current? 0 SI unit of measurement is ampere. 0 For short amps 0 Symbol: “A” or “mA” for milliamps.

8. Let’s Review 0 What is Voltage?

9. Let’s Review 0 What is Voltage? 0 the difference in electric potential energy between two points per unit electric charge. 0 Sometimes referred to as “electric potential”

10. Let’s Review 0 What is Voltage? 0 the difference in electric potential energy between two points per unit electric charge. 0 Sometimes referred to as “electric potential” 0 What is voltage measured in?

11. Let’s Review 0 What is Voltage? 0 the difference in electric potential energy between two points per unit electric charge. 0 Sometimes referred to as “electric potential” 0 What is voltage measured in? 0 measured in joules per coulomb = volts

12. Let’s Review 0 What is Resistance?

13. Let’s Review 0 What is Resistance? 0 electrical quantity that measures how the device or material reduces the electric current flow through it. 0 If we make an analogy to water flow in pipes, the resistance is bigger when the pipe is thinner, so the water flow is decreased.

14. Let’s Review 0 What is Resistance? 0 electrical quantity that measures how the device or material reduces the electric current flow through it. 0 If we make an analogy to water flow in pipes, the resistance is bigger when the pipe is thinner, so the water flow is decreased. 0 What is Resistance measured in?

15. Let’s Review 0 What is Resistance? 0 electrical quantity that measures how the device or material reduces the electric current flow through it. 0 If we make an analogy to water flow in pipes, the resistance is bigger when the pipe is thinner, so the water flow is decreased. 0 What is Resistance measured in? 0 measured in units of ohms (Ω) or kilohms (kΩ).

16. Let’s Review 0 What is a Conductor?

17. Let’s Review 0 What is a Conductor? 0 is a substance in which electrical charge carriers, usually electrons, move easily from atom to atom with the application of voltage. 0 an object or type of material that allows the flow of electrical current in one or more directions. 0 Examples?

18. Let’s Review 0 What is an Insulator?

19. Let’s Review 0 What is an Insulator? 0 a material whose internal electric charges do not flow freely, and therefore make it nearly impossible to conduct an electric current. 0 Examples?

20. Let’s Review 0 What is Ohm’s Law?

21. Let’s Review 0 What is Ohm’s Law? 0 Mathematical equation used to calculate the relationship between voltage and current in an ideal conductor. 0 This relationship states that: The potential difference (voltage) across an ideal conductor is proportional to the current through it. The constant of proportionality is called the "resistance", R.

22. Let’s Review 0 What is Ohm’s Law formula/equation to solve for Current?

23. Let’s Review 0 What is Ohm’s Law formula/equation to solve for Current?

24. Let’s Review 0 What is Ohm’s Law formula/equation to solve for Voltage?

25. Let’s Review 0 What is Ohm’s Law formula/equation to solve for Voltage?

26. Let’s Review 0 What is Ohm’s Law formula/equation to solve for Resistance?

27. Let’s Review 0 What is Ohm’s Law formula/equation to solve for Resistance?

28. Pause…. Let’s Review 0 Why is current represented as “I”? 0 The conventional symbol for current is I, which originates from the French phrase intensité de courant, meaning current intensity 0 The I symbol was used by André-Marie Ampère, after whom the unit of electric current is named, in formulating the eponymous Ampère's force law, which he discovered in 1820.

29. Pause…. Let’s Review 0 Why is voltage represented as “V”? 0 The volt (symbol: V) is the derived unit for electric potential, electric potential difference (voltage), and electromotive force. 0 The volt is named in honour of the Italian physicist Alessandro Volta (1745–1827), who invented the voltaic pile, possibly the first chemical battery.

30. Let’s Review 0 Using a Multimeter

31. For Reference: 0 My Website: dremarysol.wordpress.com/mart318/ dremarysol.wordpress.com/mart318/ 0 Multimeter.pdf 0 New Multimeter Diagram 0 Basic Household Tests for Practice

32. Moving On…

33. Electric Circuits!! 0 Made up of two elements: 0 a power source and components that convert the electrical energy into other forms of energy. 0 We build electrical circuits to do work, or to sense activity in the physical world. 0 physical computing

34. Electric Circuits 0 Every circuit has to have a source of electrical energy and a load that uses the energy. 0 All of the electrical energy in a circuit has to get used by the load. 0 The load will convert the electrical energy to some other form of energy.

35. Electric Circuits 0 A circuit with no load is called a short circuit. 0 In a short circuit, the power source feeds all of its power through the wires and back to itself, and either the wires melt (if you’re lucky), or the battery and the components blow up.

36. Electric Circuits 0 Basic circuit: consisting of a lamp, a pushbutton, and a battery. 0 The battery is the source and the lamp is the load.

37. Types of Electric Circuits 0 There are two common kinds of circuits: 0 Direct Current (DC) 0 Alternating Current (AC) 0 In a DC circuit, current always flows one direction. 0 In an AC circuit, the direction of current flow is reversed in a regular repeating cycle.

38. Schematic Diagrams 0 Schematic diagrams are diagrams of circuits that represent the electrical relationships between the components in the circuit. 0 A schematic doesn’t always show the spatial arrangement of the components; it’s arranged so that you can best understand the flow of the electricity.

39. Schematic Diagrams 0 In the diagram on the right, the whole circuit is shown as a loop, with the battery (marked V1) to the left of the loop. 0 In the diagram on the left, the circuit is not shown as a loop.

40. Schematic Symbols 0 Ground is the place in a circuit with where the potential energy of the electrons is zero.

41. Schematic Symbols 0 Resistors resist, but do not totally block, the flow of electricity. 0 They are used to control the flow of current. 0 Current can move either way through a resistor, so it doesn’t matter which way they’re connected in a circuit.

42. Schematic Symbols 0 Resistors

43. Schematic Symbols 0 Diodes permit the flow of electricity in one direction, and block it in the other direction. 0 Because of this, they can only be placed in a circuit in one direction. 0 Light-Emitting Diodes (LED’s) are special types of diodes which emit light when current flows through them.

44. Schematic Symbols 0 Diodes

45. Schematic Symbols 0 Switches and pushbuttons control the flow of current through a junction in a circuit:

46. Controlling The Direction 0 Electrical components can be arranged in a circuit so that the energy flows through one to the other, or they can be arranged so that the energy is split, flowing through both at the same time.

47. Controlling The Direction 0 Series: 0 When the energy flows from one to the other, the components are in. 0 Parallel: 0 When it flows through them at the same time, they are in.

48. Controlling The Direction 0 Series:

49. Controlling The Direction 0 Parallel:

50. About Current 0 Current tends to follow the path of least resistance to the ground. 0 So if it has a choice of two paths in a circuit, and one has less resistance, that’s the path it’ll take. 0 Each component that offers a resistance lowers the voltage, and by the time you reach the end of the circuit loop, there will be no voltage left. 0 The amount of current going into any point in a circuit is the same as the amount coming out of that point.

51. Resource for Current & Schematic Diagrams 0 www.falstad.comwww.falstad.com