1. UNIT 6 ELECTRICITY

2. WE HAVE AN OBJECT, A MATERIAL…

3. WE USE A MICROSCOPE…

4. WE CAN SEE…

5. IF WE COULD SEE A SMALLER PART…

7. Electrons are responsible of electricity!!!!!
HOW???

8. 1. ELECTRICITY
Electric charge is a property of all objects and is responsible for electrical phenomena.

9. These phenomena are caused by the electrical forces of attraction and repulsion

10. ATTRACTION
John Mary

11. REPULSION
Peter Celia

12. REPULSION
ATRACTION
Two objects with the same charge repel each other. Two objects with different charge atract each other

13. TWO POSSIBILITIES
a)-STATIC ELECTRICITY
b)-ELECTRIC CURRENT

14. a)-STATIC ELECTRICITY

15. b)Electric current
Electric current is a continuous movement of electrons

16. Materials that allow electric current to pass through them.
CONDUCTORS
Materials that allow electric current to pass through them.
Copper, Silver, Aluminum

17. Materials that don’t allow electric current to pass through them.
INSULATORS
Materials that don’t allow electric current to pass through them.
Plastic, Ceramic, Wood

18. What produces an electric current?
IMBALANCE: There must be an imbalance between two points of a conductor

19. 1.1. ELECTRIC CIRCUITS
An electric circuit is a set of connected components through which an electric current circulates.

21. 1 -something to move electrons A generator

22. 2 -something to transform electrical energy:A bulb, a motor, a bell… A receptor A receptor transform electrical energy into another type of energy

23. 3 -conductor A wire…

24. 4 –control and protection components… A switch, a push button…
Control component: stop, start or change the direction of the electric current
Protection component:stops the current when it´s too strong.

25. SYMBOLS
Bulb
Switch
Push switch
Battery
Motor

26. 1.2. Effects of electric current

27. a) Heat
Electrons crash into the atoms and part of the energy is transformed into heat

28. b) Light
When the temperature of an object increases a lot, light begins to appear.

29. c) Motion
Motors transform electrical energy into motion.

30. Page 129
Exercises 3, 5, 6, 7

31. 2. ELECTRIC QUANTITIES CHARGE (Q) COULOMBS
It’s the amount of electricity stored in an object

32. ELECTRIC QUANTITIES VOLTAGE (V)
It’s the difference between the electrical energy at two points in a circuit.

33. ELECTRIC QUANTITIES CURRENT (I)
It’s the number of electrons that pass through a specific point in one second.

34. ELECTRIC QUANTITIES RESISTANCE (R)
It’s the oposition of the components of a circuit to the flow of the electric current.

35. 2.1. MEASURING INSTRUMENTS
VOLTIMETER: measures the electrical voltage (in volts)

36. POLYMETER: measures different electric quantities (voltage, current, resistance) on different scales.

37. 2.2. OHM´S LAW
Is the proportional relationship between voltage, current and resistance.
V: voltaje (v)
I: current (A)
R: resistance (Ω)

39. Page 131
Exercises 10, 13, 14, 15
Page 132
Exercises 1, 3, 5, 6