Electricity Practical Example and Experiment

1. Electricity Practical Example and Experiment www.assignmentpoint.com

2. Electricity • Charges • Electrons • Voltage • Current • Series • Parallel • Resistance The slides are designed to tie in with a set of worksheets, but could be adapted or serve as a template for other teachers www.assignmentpoint.com

3. rubbing it with a duster/pulling it through my hair • I charged up a plastic comb by • When I put the charged-up comb near some foil the foil jumped up to stick to the comb www.assignmentpoint.com

4. yes yes yes no yes no www.assignmentpoint.com Text

5. The electroscope Stop! www.assignmentpoint.com

6. Rises up Rises up Rises up Rises up If an uncharged object is brought near an electroscope the gold leaf If a charged object is brought near an electroscope the gold leaf doesn’t move. rises up. www.assignmentpoint.com

7. Pulling and Pushing Pull together Push apart Pull together Push apart Pull together Push apart www.assignmentpoint.com

8. Is there a pattern? different Pull together Pull together same Push apart Push apart different Pull together Pull together same Push apart Push apart Pull together different Pull together same Push apart Push apart www.assignmentpoint.com

9. 5. If the charged objects are the same material then they will repel www.assignmentpoint.com

10. The centre of the atom contains both yellow neutrons and green positive protons Around the outside are the negative electrons Topic 7 page 7 Where Does Charge Come From? www.assignmentpoint.com

11. 1. There are kinds of electrical charge called 2.a) To make an object positively charged you need to b) To make an object negatively charged you need to 3. If a substance is neutral it means that two positive and negative remove negative charges add negative charges the negative charges are exactly balanced by the positive charges www.assignmentpoint.com

12. 4. Two charged polythene rods will repel because 5. A cleaned mirror will be dusty within 24hrs because 6. A woolen jersey could be attracted to a nylon shirt because they have the same charge the charge attracts dust they would have opposite charges which would attract www.assignmentpoint.com

13. A Van de Graff generator • a) Your hair stands on end when you • touch a Van de Graff generator • because • b) Your hair goes down when you touch a • water tap because Topic 7 page 10 builds up and stores a negative charge your hairs become negatively charged and repel each other the negative charges leave you flowing along the pipes to the ground and the hairs stop repelling www.assignmentpoint.com

14. - - - - - - - - - - - moving current When a flows, charges are Now fill the blanks www.assignmentpoint.com

15. A Battery Switch Ammeter Bulb www.assignmentpoint.com

16. Part of circuitStatement Battery measures current Bulb pushes the current Switch changes electrical energy to light Ammeter carries current round circuit Connecting wire turns the current on and off www.assignmentpoint.com

17. Dim bulb Bright bulb – small current - large current The a bulb the bigger the brighter current www.assignmentpoint.com

18. a) An electric circuit • b) A complete circuit has • 5. A B C D is a path that electricity can flow along no gaps allowing electricity to flow along it 0.2A 0.5A 0.65A 0.95A www.assignmentpoint.com

19. A A A. www.assignmentpoint.com

20. A A B. www.assignmentpoint.com

21. V V C. www.assignmentpoint.com

22. 2a)The battery b) The wires c) The ammeter d) The switch 3a) The energy change in the bulb is b) The energy change in the battery is 4a) Electricians use symbols to pushes the current through the wires conduct the electricity measures the current opens and closes a gap Electrical energy  Light energy Chemical energy  Electrical energy make their diagrams clearer and tidier www.assignmentpoint.com

23. A A A X 0.2 0.2 A Z Y 0.2 A 0.2 0.2 0.2 In a series circuit the current is the at all points in the circuit. same www.assignmentpoint.com

24. A A A 0.4 Z X 0.2 Y 0.2 In a parallel circuit the current taken from the battery the sum of the currents through the two bulbs 0.2 0.2 equals 0.4 www.assignmentpoint.com

25. Q1. The two bulbs in circuit B make less light than the one bulb in circuit A because Q2. No current flows in circuit C becauseQ3. Q4. House lights are better wired in parallel than series; a) b) B shares the current between two (dim) bulbs one of the bulbs is blown creating a break in the circuit Broken bulb doesn’t put whole house into darkness don’t dim www.assignmentpoint.com

26. V A Using Voltmeters and Ammeters Voltmeter – connected in parallel Ammeter connected in series www.assignmentpoint.com

27. V Correctly Wired? No! The voltmeter has been connected in series – it should be parallel www.assignmentpoint.com

28. A Correctly Wired? No the Ammeter has been connected in parallel – it should have been series www.assignmentpoint.com

29. A Correctly Wired? Yes! This Ammeter has been connected correctly in series www.assignmentpoint.com

30. A Correctly Wired? Yes! This Ammeter has been connected correctly in series www.assignmentpoint.com

31. V Correctly Wired? Yes! The Voltmeter has been connected correctly in parallel www.assignmentpoint.com

32. A Correctly Wired? Yes! The Ammeter has been connected correctly in series www.assignmentpoint.com

33. Effects of Series? As more bulbs are added in series the bulbs grow dimmer www.assignmentpoint.com

34. Circuit Diagram Iron Plastic Brass Rubber Copper Perspex Steel Glass Graphite Wood www.assignmentpoint.com

35. Electric fire Glows red hot Conducts doesn’t get hot Conducting wires Safety fuse Heats up and melts www.assignmentpoint.com

36. dim 1.5 V brighter 6 V 12 V bright When the voltage increases the current increases www.assignmentpoint.com

37. 5. Write down your ideas. • The more batteries the brighter the bulb • This holds true as long as the batteries face the same way • If batteries are reversed they cancel each other out Elephant handout www.assignmentpoint.com

38. Topic 7 page 29 Text Animation 1 www.assignmentpoint.com

39. Title: Aim: Method: Choosing the best type of cable To compare copper/nichrome, thick/thin, long/short wires and find the best Test thick and thin wires in a circuit and measure how it affects the current using an ammeter. Then test copper/nichrome and long/short wires. www.assignmentpoint.com

40. A Diagram: Results: A bulb may be used instead of an ammeter www.assignmentpoint.com

41. Conclusion: • Short wires are better than long wires. • Copper wires are better than nichrome wires. • Thick wires are better than thin wires. www.assignmentpoint.com

42. Copper has a resistance than nichrome Thin wires have resistance than thick ones Longer wires have resistance than short ones lower higher higher www.assignmentpoint.com

43. The variable resistor 4. Write down what you found out. The longer the wire (coil) the dimmer the bulb, the shorter the wire the brighter the bulb. www.assignmentpoint.com

44. The variable resistor Write down what you found out. The longer the wire (coil) the smaller the current and the dimmer the bulb. The longer wire has a higher resistance. www.assignmentpoint.com

45. A long thin nichrome wire has a higher resistance because • a) Thick copper wires are good for carrying current because • b) Long thin coils of nichrome are used in electric fires because thick has a lower resistance, as does copper and short wires. copper is a good conductor and thick wires have low resistance nichrome has a high resistance causing it to heat up without melting www.assignmentpoint.com

46. 3. A variable resistor is used to 4. When the volume on a radio is turned Down 5. Cookers need thick cabling increase and decrease the current by changing the length of a resistance wire the resistance wire is lengthened, causing a reduction in the current. because they use much more current than lamps www.assignmentpoint.com

47. Topic 7 page 36 The purpose of a fuse is to protect you from a short circuit - safety Not to make the device work www.assignmentpoint.com

48. V A Circuit Symbols(components used in slides) You can find more downloads and help at www.lab6.co.uk www.assignmentpoint.com