X PHYSICS
UNIT – VIII
MAGNETISM (Paper 1)
1. The idea of magnetism was first proposed by _________________.
2. Ewing’s theory is called as ______________
3. ______________ magnetic substances do not exist.
4. Magnetic poles always exist in ______________.
5. Any magnet consisting of poles is also called ______________.
6. A magnet can be demagnetized by ______________.
7. In a steel the ailments of _________ produced during the magnetisation remains permanent. 8. The ability of a pole of magnet to attract or repel another magnetic pole is called its _______.
9. Magnetic permeability is denoted by ______________.
10. The value of magnetic permeability of free space µo = ______________. 11. ______________ is the unit of magnetic pole strength in S.I. system.
12. Unit for pole strength in M.K.S. system is ______________.
13. For air or vacuum µr = ______________.
14. The µo is ______________ anywhere in air or vacuum.
15. Relation between H, m, r2 in S.I. system is _______________.
16. 1 Weber = ______________.
17. Units of H in S.I. System is ______________.
18. Units of H in C.G.S. system is ______________.
19. The units of intensity of magnetization are ______________
20. Magnetic moment of a bar magnet is given by ______________.
21. The S.I. Units of magnetic moments are ______________.
22. Magnetic moment per unit volume is called ______________.
23. The equatorial line is ______________.
24. The magnetic moment denoted by M is defined for the ______________ magnet.
25. A pole strength ‘m’ in a field of induction B experience a force of ______________.
26. The value of Bo in Andhra Pradesh is about ______________.
27. When the south pole of the bar magnet facing North pole of the earth, the null points are formed on ______________.
28. When null points are formed on axial line the magnetic moment. (M) = ______________.
29. According to the inverse square law B decreases with distance while Bo remains ________.
30. The line joining the two poles is ______________.
31. The magnetic moment acquired by a substance per unit volume is defined as __________.
32. All materials can be classified into _____________ magnetic materials.
33. The relative permeability µr for a diamagnetic substance is approximately equal to ________.
34. Oxygen, solution of slats of nickel, manganese, aluminium, platinum and chromium are some of the _____________ substances.
35. _____________ substances are those in which the resultant magnetic moment of individual atoms is zero.
36. Manganese is an example for _____________ magnetic material.
37. The relative permeability of _____________ material is slightly greater than on (µr>1).
38. ______________of ferro – magnetic material is very high µr >> 1.
39. The unit of magnetic induction is ____________.
40. A molecule consists of two or more ____________ .
41. In each atom ____________ revolve round the nucleus in orbits.
42. Electron carries ____________ charge.
43. The electric current produces a ____________ field.
44. The magnet is said to have ____________.
45. The spin motion of an electron also gives rise to a ____________.
46. In the case of non-magnetic substance like wood the net magnetic moment due to the molecule is ____________.
47. The cause for magnetism in a steel magnet is due to the ____________.
48. Iron is ferromagnetic below ____________.
49. An electromagnet is made of ____________.
50. Permanent magnets are made of ____________.
51. Retentivity is more for ____________.
52. When a charged body moves in an orbit ____________ is produced.
53. The magnetic susceptibility of a para magnetic substance is ____________.
54. The ferromagnetic substances are strongly attracted by a ____________.
55. The ferromagnetic substances align themselves easily in the direction of the applied _______.
56. Strictly speaking diamagnetism is a ____________ property.
57. The S.I. Unit of magnetic induction is ____________.
58. The magnetic property which has no units is ____________.
59. The magnetic nature of a substance is determined by ____________.
60. One Tesla = ____________.
X PHYSICS
UNIT – VIII
MAGNETISM (Key )
(1) Weber (2) molecular theory of magnetism (3) Isolated (4) pairs (5) magnetic dipole (6) tapping or harming or heating (7) molecular magnets (8) pole strength (9) µ (10) 4? × 10-7 henry / metre (11) Ampere – metre (12) Weber (13) one (14) constant (15) H = m/4pr2 (16) µo A – m (17) Ampere – metre (18) gauss (19) ampere/metre or Weber/metre (20) M=2lm(A-m2) (21) ampere – metre2 (22) intensity of magnetization (23) Perpendicular (24) bar (25) mB (26) 0.39 × 10–4 Tesla (27) axial line (28) 195 d3 A-m2 (29) constant (30) magnetic axis.
(31) intensity of Magnetisation (32) dia, para and ferro (33) 1 (4) paramagnetic (35) Dia-magnetic (36) para (37) para-magnetic (38) Relative permeability µr (39) Tesla or wb.m–2 (40) atoms (41) electrons (42) negative (43) magnetic (44) magnetic moment (45) magnetic behaviour (46) zero (47) spin of electrons (48) 770oC (49) soft iron (50) steel (51) steel (52) magnetic field (53) small (54) magnet (55) magnetic (56) Universal (57) Tesla (58) Magnetic Susceptibility (59) spin of its electrons (60) 104 gauss.
