1. To return to the chapter summary click Escape or close this document. gpscience.com Image Bank Foldables Video Clips and Animations Standardized Test Practice 8 8 Chapter Resources Click on one of the following icons to go to that resource. Chapter Review Questions Chapter Summary

2. To return to the chapter summary click Escape or close this document. 5 5 Chapter Resources gpscience.com

3. To return to the chapter summary click Escape or close this document. Image Bank Click on individual thumbnail images to view larger versions. 8 8

4. To return to the chapter summary click Escape or close this document. Image Bank To transfer images to your own power point follow the following steps: Open the “Resource” file from the CD-ROM disc – view the file in the “normal view” or “slide sorter view” mode - go to slide #2 – from there you can click through the images and follow these instructions. Click once on the image. Copy the image Go to your own power point document Paste the image. Transfer Images 8 8

5. To return to the chapter summary click Escape or close this document. Image Bank Magnetite 8 8

6. To return to the chapter summary click Escape or close this document. Image Bank Magnetic Field 8 8

7. To return to the chapter summary click Escape or close this document. Image Bank Horseshoe and Disk Magnets 8 8

8. To return to the chapter summary click Escape or close this document. Image Bank Compass Needles on a Bar Magnet 8 8

9. To return to the chapter summary click Escape or close this document. Image Bank Compass Needle Alignment 8 8

10. To return to the chapter summary click Escape or close this document. Image Bank Magnetic Nail 8 8

11. To return to the chapter summary click Escape or close this document. Image Bank Magnetic Domains 8 8

12. To return to the chapter summary click Escape or close this document. Image Bank Broken Magnetic Poles 8 8

13. To return to the chapter summary click Escape or close this document. Image Bank Magnetic Field Current in Wire 8 8

14. To return to the chapter summary click Escape or close this document. Image Bank Magnetic Field Wire Loop 8 8

15. To return to the chapter summary click Escape or close this document. Image Bank Magnetic Field Wire 8 8

16. To return to the chapter summary click Escape or close this document. Image Bank Magnetic Iron Core 8 8

17. To return to the chapter summary click Escape or close this document. Image Bank Speaker 8 8

18. To return to the chapter summary click Escape or close this document. Image Bank Electromagnet 8 8

19. To return to the chapter summary click Escape or close this document. Image Bank Galvanometer 8 8

20. To return to the chapter summary click Escape or close this document. Image Bank Fan 8 8

21. To return to the chapter summary click Escape or close this document. Image Bank Electric Motor 8 8

22. To return to the chapter summary click Escape or close this document. Image Bank Turning Motor 8 8

23. To return to the chapter summary click Escape or close this document. Image Bank Current Direction Change 8 8

24. To return to the chapter summary click Escape or close this document. Image Bank Motor Forces 8 8

25. To return to the chapter summary click Escape or close this document. Image Bank Concept Map-Left 8 8

26. To return to the chapter summary click Escape or close this document. Image Bank Concept Map 8 8

27. To return to the chapter summary click Escape or close this document. Image Bank Power Plant 8 8

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29. To return to the chapter summary click Escape or close this document. Image Bank Alarm Clock 8 8

30. To return to the chapter summary click Escape or close this document. Image Bank Power Lines 8 8

31. To return to the chapter summary click Escape or close this document. Image Bank Transformer 8 8

32. To return to the chapter summary click Escape or close this document. Image Bank Step Down Transformer 8 8

33. To return to the chapter summary click Escape or close this document. Image Bank Creating Electricity 8 8

34. To return to the chapter summary click Escape or close this document. Foldables Using Magnets Many devices you use contain magnets that help convert one form of energy to another. Make the following Foldable to help you understand how magnets are used to transform electrical and mechanical energy. 8 8

35. To return to the chapter summary click Escape or close this document. Foldables Fold a sheet of paper in half lengthwise. 8 8

36. To return to the chapter summary click Escape or close this document. Foldables Fold the paper down about 2 cm from the top. 8 8

37. To return to the chapter summary click Escape or close this document. Foldables Open and draw lines along the top fold. Label as shown. 8 8

38. To return to the chapter summary click Escape or close this document. Foldables As you read the chapter, summarize how magnets are used to convert electrical energy to mechanical energy in the left column, and how magnets are used to convert mechanical energy to electrical energy in the right column. Summarize 8 8

39. To return to the chapter summary click Escape or close this document. Click image to play movie 8 8 Video Clips and Animations To view the next video clip or animation click here. clip

40. To return to the chapter summary click Escape or close this document. Click image to play movie 8 8 Video Clips and Animations

41. To return to the chapter summary click Escape or close this document. 8.1 Reviewing Main Ideas A magnetic field surrounds a magnet and exerts a magnetic force. Magnetism All magnets have two poles: a south pole and a north pole. Opposite poles of magnets attract; like poles repel. Groups of atoms with aligned magnetic poles are called magnetic domains.

42. To return to the chapter summary click Escape or close this document. 8.2 Reviewing Main Ideas An electric current flowing through a wire produces a magnetic field. Electricity and Magnetism An electric current passing through a coil of wire can produce a magnetic field inside the coil. The coil becomes an electromagnet. One end of the coil is the north pole, and the other end is the south pole.

43. To return to the chapter summary click Escape or close this document. 8.2 Reviewing Main Ideas The magnetic field around an electromagnet depends on the current and the number of coils. Electricity and Magnetism An electric motor contains a rotating electromagnet that converts electrical energy to mechanical energy.

44. To return to the chapter summary click Escape or close this document. 8.3 Reviewing Main Ideas By moving a magnet near a wire, you can create an electric current in the wire. This is called electromagnetic induction. Producing Electric Current A generator produces electric current by rotating a coil of wire in a magnetic field.

45. To return to the chapter summary click Escape or close this document. 8.3 Reviewing Main Ideas Producing Electric Current Direct current flows in one direction through a wire; alternating current reverses the direction of current flow in a regular pattern. The number of turns of wire in the primary and secondary coils of a transformer determines whether it increases or decreases voltage.

46. To return to the chapter summary click Escape or close this document. Question 1 Chapter Review What do magnetic field lines connect? A. magnetic domains B. north pole and south pole of a magnet C. north poles within a magnetic domain D. south poles within a magnetic domain 8 8

47. To return to the chapter summary click Escape or close this document. Answer 8 8 Chapter Review The answer is B. The magnetic field can be represented by lines of force, or magnetic field lines.

48. To return to the chapter summary click Escape or close this document. Question 2 What two things are found on all magnets? 8 8 Chapter Review

49. To return to the chapter summary click Escape or close this document. Answer 8 8 Chapter Review All magnets have two poles: a south pole and a north pole.

50. To return to the chapter summary click Escape or close this document. Question 3 8 8 A. domain B. pole C. solenoid D. turbine Chapter Review Which of these is a single wire wrapped into a cylindrical wire coil?

51. To return to the chapter summary click Escape or close this document. Answer 8 8 Chapter Review The answer is C. When current flows through a solenoid, the magnetic field inside it is stronger than the magnetic field inside a single loop.

52. To return to the chapter summary click Escape or close this document. Question 4 8 8 Why are electromagnets temporary magnets? Answer Chapter Review An electromagnet is a temporary magnet because the magnetic field is present only when current is flowing in the solenoid.

53. To return to the chapter summary click Escape or close this document. Question 5 8 8 A. alternating current B. direct current C. electromagnet D. magnetic domain Chapter Review Which reverses the direction of current in a regular pattern?

54. To return to the chapter summary click Escape or close this document. Answer 8 8 Chapter Review The answer is A. Alternating current reverses the direction of current in a regular pattern. Direct current flows in only one direction through a wire.

55. To return to the chapter summary click Escape or close this document. Standardized Test Practice Question 1 A. aluminum foil B. nail in contact with a magnet C. normal iron nail D. glass 8 8 Which is best represented by the diagram?

56. To return to the chapter summary click Escape or close this document. Standardized Test Practice Answer 8 8 The answer is B. A normal iron nail’s microscopic domains are arranged randomly. Contact with a magnet causes them to become temporarily aligned.

57. To return to the chapter summary click Escape or close this document. Standardized Test Practice Question 2 Which is true of a temporary magnet? A. A magnetic field prevents the domains from aligning. B. A magnetic field causes domains to align. C. The domains cannot return to random alignment after a magnetic field is removed. D. Randomly aligned domains cannot be aligned. 8 8

58. To return to the chapter summary click Escape or close this document. Standardized Test Practice Answer 8 8 The answer is B. In a temporary magnet, the domains return to random alignment when the field is removed.

59. To return to the chapter summary click Escape or close this document. Standardized Test Practice Question 3 8 8 A transformer has 50 turns of wire in the primary coil and 250 turns of wire in the secondary coil. The output voltage is 120 V. What is the input voltage? A. 240 V B. 24 V C. 12 V D. 6 V

60. To return to the chapter summary click Escape or close this document. Standardized Test Practice Answer 8 8 The answer is B. This is a step-up transformer that has 5 times as many turns of wire in the secondary coil as the primary coil has.

61. To return to the chapter summary click Escape or close this document. Standardized Test Practice Question 4 8 8 What is the output voltage from a transformer if a direct current flows through the primary coil? A. half the input voltage B. ten times the input voltage C. twice the input voltage D. zero

62. To return to the chapter summary click Escape or close this document. Standardized Test Practice Answer 8 8 The answer is D. If direct current flows through the primary coil, the direction of the field does not change. It is the changing magnetic field that induces an alternating current in the secondary coil.

63. To return to the chapter summary click Escape or close this document. Standardized Test Practice Question 5 8 8 A transformer has 400 turns of wire in the primary coil and 20 turns of wire in the secondary coil. If the input voltage is 440 V, what is the output voltage? A. 440 V B. 220 V A. 120 V B. 22 V

64. To return to the chapter summary click Escape or close this document. Standardized Test Practice Answer 8 8 The answer is D. In this step-down transformer, the input voltage is twenty times the output voltage.

65. To return to the chapter summary click Escape or close this document. 8 8 To advance to the next item or next page click on any of the following keys: mouse, space bar, enter, down or forward arrow. Click on this icon to return to the table of contents Click on this icon to return to the previous slide Click on this icon to move to the next slide Click on this icon to open the resources file. Help Click on this icon to go to the end of the presentation.

66. To return to the chapter summary click Escape or close this document. End of Chapter Resources File