1. MAGNETISM

2. MAGNETISM –THE ABILITY OF CERTAIN MATERIALS TO ATTRACT IRON, COBALT OR NICKEL.

3. CLASSIFICATION OF MAGNETS
NATURAL MAGNETS
ARTIFICIAL PERMANENT MAGNETS
ELECTROMAGNET

4. NATURAL MAGNET -EARTH

5. NATURAL MAGNETS--LODESTONES

6. LODESTONES BECAME MAGNETIZED BY LYING IN THE EARTH’S MAGNETIC FIELD FOR THOUSANDS OF YEARS

7. THE SPHERE OF ARCHIMEDES
THE ANCIENT GREEKS RECOGNIZED THE MAGNETISM OF LODESTONES MORE THAN 2500 YEARS AGO
THE SPHERE OF ARCHIMEDES

8. ARTIFICIAL PERMANENT MAGNETS
HARD STEEL
MAGNETIC COMPASS
ALNICO

9. HARD STEEL—HORSHOE MAGNET

10. MAGNETIC COMPASS
The magnetic compass was brought to Europe in the Middle Ages from the Chinese who had been using the compass for over 1500 years

11. ALNICO—ALLOY OF:
AL—ALUMINIUM
NI—NICKEL
CO—COBALT

12. ALUMINUM CAN NOT BE MAGNETIZED

13. ALNICO—SUPER STRONG MAGNETS

14. ELECTROMAGNETS TEMPORARY MAGNETS PRODUCED BY MEANS OF ELECTRIC CURRENT.

15. ELECTROMAGNET

16. MRI ELECTROMAGNET

17. LAWS OF MAGNETISM EVERY MAGNET HAS TWO POLES
LIKE MAGNETIC POLES REPEL: UNLIKE POLES ATTRACT
THE FORCE OF ATTRACTION OR REPULSION FOLLOWS INVERSE SQUARE LAW ( NOT ACCURATE)

18. EVERY MAGNET HAS TWO POLES- NORTH & SOUTH

19. LIKE MAGNETIC POLES REPELEACH OTHER UNLIKE POLES ATTRACT EACH OTHER

20. THE FORCE OF ATTRACTION OR REPULSION BETWEEN TWO MAGNETSPp
F = k d2
THE FORCE IS PROPORTIONAL TO THE PRODUCT OF THE MAGNETIC POLE STRENGTHS DIVIDED BY THE SQUARE OF THE DISTANCE BETWEEN THEM

21. NATURE OF MAGNETISM

22. BREAKING A MAGNET WILL RESULT IN EACH FRAGMENT BECOMING A WHOLE MAGNET

23. HEATING OR HAMERING STEEL IN PROXIMITY TO A MAGNET –WILL MAGNETIZE IT.
STROKING OF IRON WITH MAGNET WILL MAGNETIZE IT
GENTLY JARRING A TEST TUBE OF IRON FILINGS NEAR A MAGNET WILL MAGNETIZE IT

24. MAGNETIZATION

25. AN ELECTRIC CHARGE SPINNING ON ITS AXIS WILL CREATE MAGNETIC FIELD

26. MOVING CHARGED PARTICLE WILL INDUCE MAGNETIC FIELD

27. THE SMALL MAGNET CREATED BY ELECTRON ORBIT IS CALLED A MAGNETIC DIPOLE

28. ACCUMULATION OF MANY ATOMIC MAGNETS WITH THEIR DIPOLES ALIGNED CREATES A MAGNETIC DOMAIN

29. THE MAGNETIC DIPOLES IN BAR MAGNET GENERATE IMAGINARY LINES OF THE MAGNETIC FIELD

30. MAGNETIC LINES OF FORCE ARE CLOSE LOOPS

31. MAGNETIC LINES OF FORCE EARTH

32. MAGNETIC LINES OF FORCE BAR MAGNET

33. THE STRENGTH OF MAGNETIC FIELD IS EXPRESSED IN SI UNIT TESLA
1 TESLA = 10,000 GAUSSES

34. MAGNETIC ELEMENT TWO OR MORE ELECTRONS SPINNING IN THE SAME DIRECTION
NUCLEUS

35. A MAGNETIC ELEMENT CAN EXISTS EITHER IN MAGNETIZED OR NON-MAGNETIZED STATE

36. MAGNETIZED MAGNETIC MATERIAL

37. NON-MAGNETIZED MAGNETIC MATERIAL

39. IN NONMAGNETIC MATERIALS JUST AS MANY ELECTRONS SPIN IN ONE DIRECTION AS IN OTHER. THEIR OPPOSING MAGNETIC FIELDS CANCEL OUT
NUCLEUS

40. AURORA BOREALIS

42. CHARACTERISTICS OF THE LINES OF FORCE
FROM NORTH TO SOUTH OUSIDE THE MAGNET IN THE SPACE
FROM SOUTH TO NORTH INSIDE THE MAGNET
IF IN THE SAME DIRECTION THEY WILL REPEL
MAGNETIC FIELD IS DISTORTED BY MAGNETIC MATERIALS BUT NOT AFFECTED BY NON-MAGNETIC MATERIALS

43. LINES OF FORCE

44. LINES OF FORCE
REPEL
N S
N S

45. LINES OF FORCE
ATTRACT
S N
N S

46. NONMAGNETIC MATERIALS DO NOT AFFECT THE LINES OF FORCE OF MAGNETIC FIELD

47. MAGNETIC MATERIALS LIKE IRONAFFECT THE LINES OF FORCE

48. MAGNETIC INDUCTION (MAGNETIZATION)

49. MAGNETIZATION –DOMAINS MOVE

50. MAGNETIC PERMEABILITY
EASE WITH WHICH A GIVEN MATERIAL CAN BE MAGNETIZED

51. MATERIAL RESISTANCE TO MAGNETIZATION
MAGNETIC RETENTIVITY
MATERIAL RESISTANCE TO MAGNETIZATION

52. SOFT IRON HIGH PERMEABILITY LOW RETENTIVITY

53. HARD STEEL LOW PERMEABILITY HIGH RETENTIVITY

54. “EASY COME—EASY GO”

55. MAGNETIC CLASSIFICATION OF MATTER
FERROMAGNETIC
PARAMAGNETIC MATERIALS
NONMAGNETIC MATERIALS
DIAMAGNETIC MATERIALS

56. FERROMAGNETIC MATERIALS –IRON, COBALT, NICKEL
FERROMAGNETIC MATERIALS –IRON, COBALT, NICKEL. STRONGLY ATTRACTED BY MAGNETS

57. PARAMAGNETIC MATERIALS—PLATINUM. FEEBLY ATTRACTED BY MAGNETS

58. NONMAGNETIC MATERIALS—COPPER, WOOD, GLASS
NONMAGNETIC MATERIALS—COPPER, WOOD, GLASS. THEY ARE NOT ATTRACTED TO MAGNETS.

59. DIAMAGNETIC MATERIALS—BERYLLIUM & BISMUTH. FEEBLY REPELLED BY MAGNETS

60. DETECTION OF MAGNETISM ---COMPASS
GEOGRAPHIC NORTH POLE IS MAGNETIC SOUTH POLE?????
S. MAGNETIC
N. GEOGRAPHIC
S. GEOGRAPHIC
N. MAGNETIC

61. SMALL MAGNETS