(i) vector quantity
(ii) scalar quantity
(iii) phasor
(iv) none of above
2. The major advantage of impermanent magnets is that we can
(i) change the magnetic flux
(ii) use any magnetic material
(iii) decrease the hysteresis loss
(iv) none of above
3. Magnetic material use in stable magnets is
(i) iron
(ii) soft steel
(iii) nickel
(iv) hardened steel
4. One weber is able to
(i) 102 lines
(ii) 4π x 10-7 Lines
(iii) 1012 lines
(iv) 108 lines
5. When relative permeability of a material is a little less than I, It is call a
(i) diamagnetic material
(ii) paramagnetic material
(iii) ferromagnetic material
(iv) none of the above
6. When magnet is intense
(i) it gains magnetism
(ii) it loses magnetism
(iii) it neither loses nor gins magnetism
(iv) none of the above
7. When relative permeability of material is greatly greater than 1, it is called
(i) diamagnetic material
(ii) paramagnetic material
(iii) ferromagnetic material
(iv) none of above
8. Magnetic field intensity is a
(i) scalar quantity
(ii) vector quantity
(iii) phasor
(iv) none of the above
9. Which of following is added proper for core of an electromagnet
(i) soft iron
(ii) air
(iii) steel
(iv) tungsten steel
10. Magnetic material use in impermanent magnets is
(i) hardened steel
(ii) cobalt steel
(iii) soft iron
(iv) tungsten steel
10. Source of a magnetic field is
(i) an isolated magnetic pole
(ii) static electric charge
(iii) magnetic substances
(iv) current loop
12. Greater percentage of substances are
(i) diamagnetic
(ii) paramagnetic
(iii) ferromagnetic
(iv) none of the above
13. Unit of pole force is
(i) A/m2
(ii) Am
(iii) Am2
(iv) Wb/m2
14. Magnetic needle is kept in a regular magnetic field. It experience
(i) a force and a torque
(ii) a force but not a torque
(iii) a torque but not a force
(iv) neither a torque nor a force
15. AT/m is the unit of
(i) m.m.f.
(ii) reluctance
(iii) magnetizing force
(iv) magnetic flux density
16. When relative permeability of a material is slightly more than I. it is call a
(i) diamagnetic material
(ii) paramagnetic material
(iii) ferromagnetic material
(iv) none of the above
17. Magnetic flux pass more readily through
(i) air
(ii) wood
(iii) vacuum
(iv) iron
18. Magnet is kept in air surrounded through an iron ring. The magnetic lines of force as of the magnet will be
(i) crowded in the ring
(ii) crowded in air
(iii) evenly distributed
(iv) none of the above
19. Iron is ferromagnetic
(i) above 770°C
(ii) below 770°C
(iii) at all temperatures
(iv) none of the above
20. Magnetic needle is kept in a non-uniform magnetic field. It experiences
(i) a force and a torque
(ii) a force but not a torque
(iii) a torque but not a force
(iv) neither a force nor a torque
21. Relative permeability of a material is 0.9998. it is
(i) diamagnetic
(ii) paramagnetic
(iii) ferromagnetic
(iv) none of the above
22. Demagnetising of magnets can be done through
(i) rough handling
(ii) heating
(iii) magnetizing in opposite direction
(iv) all of the above
23. Relative permeability of iron is of order of
(i) zero
(ii) 104
(iii) 1
(iv) 10
24. Magnetic field is cause by
(i) stationary charge
(ii) a moving positive charge only
(iii) a moving negative charge only
(iv) moving positive and negative charges both
25. Charged particle enter a magnetic field perpendicular to magnetic lines of force. The path of the particle is
(i) straight line
(ii) circular
(iii) ellipse
(iv) spiral
26. Through rising number of turns 3 times in a toroid, the magnetic flux
(i) will remain unchanged
(ii) will become three times
(iii) will reduce to one-third
(iv) none of the above
27. Which of following has the uppermost permeability?
(i) paramagnetic
(ii) diamagnetic
(iii) ferromagnetic
(iv) vacuum
28. Magnetic lines of force
(i) intersect at infinity
(ii) intersect within the magnet
(iii) cannot intersect at all
(iv) none of the above
29. Unit of relative permeability is
(i) A/m
(ii) H/m
(iii) Wb/m2
(iv) none of the above
30. Distance among two magnetic poles is double and their pole strength are too doubled. The force among them
(i) increases four times
(ii) decreases four times
(iii) remains unchanged
(iv) none of the above
31. When a charged particle move through a magnetic field, it suffer a change in
(i) direction
(ii) speed
(iii) energy
(iv) no change
32. Current is accepted through a straight wire. Magnetic field established about it has magnetic lines of force
(i) circular and endless
(ii) straight
(iii) oval in shape and endless
(iv) none of the above
33. Charged particle enter a magnetic field at an angle of 30° to direction of magnetic field. Its pathway becomes
(i)) circular
(ii) straight line
(iii) elliptical
(iv) helical
34. An electron is travelling horizontally towards east. Magnetic field in vertically downward direction exert a force on electron along
(i) north
(ii) south
(iii) east
(iv) west
35. Deflection in a galvanometer fails as of 50 divisions to 20 divisions while a 12 Ω shunt is apply. Galvanometer resistance is
(i) 18Ω
(ii) 6Ω
(iii) 9Ω
(iv) 24Ω
36. Magnetic field in a moving coil galvanometer finished radial to
(i) make the field stronger
(ii) make the field weaker
(iii) make the scale linear
(iv) to reduce its resistance
37. Magnetic field inside a current moving solenoid is
(i) directly proportional to current
(ii) directly proportional to its length
(iii) inversely proportional to number of turns
(iv) inversely proportional to current
38. Strong magnetic field is applied on stationary electron. Then electron
(i) remains stationary
(ii) starts spinning
(iii) moves in the direction of field.
(iv) moves in an opposite direction
39. An electron moves by a regular velocity v and enters a region of regular magnetic field B. If v and B are parallel to each other then electron will
(i) move in a circular path
(ii) move in a direction perpendicular to B.
(iii) continue to moves in the same direction
(iv) not move at all
40. To send 10% of the major current through a galvanometer of resistance 99Ω , value of shunt resistance required is
(i) 11Ω
(ii) 33Ω
(iii) 9.9Ω
(iv) 22Ω
41. Strong magnetic field is applied to a motionless electron. Then the electron
(i) moves in the direction of field
(ii) moves in an opposite direction
(iii) remains stationary
(iv) starts spinning
42. Moving electric charge will generate
(i) electric field only
(ii) both electric and magnetic fields
(iii) magnetic field only
(iv) no field
43. The resistance of an ideal voltmeter is
(i) zero
(ii) infinite
(iii) very low
(iv) data incomplete
44. Ammeter of range 1A has a resistance of 0.9Ω. To expand range to 10A, value of shunt necessary is
(i) 0.9Ω
(ii) 0.3Ω
(iii) 0.01Ω
(iv) 0.1Ω
45. If an electron enters a consistent magnetic field obliquely, path of electron will become
(i) an ellipse
(ii) a circle
(iii) a spiral
(iv) none of above
46. Current in a wire is directed towards east and wire is sited in a magnetic field directed toward north. Force on the wire is
(i) due east
(ii) due south
(iii) vertically downward
(iv) vertically upward
47. Current flows in a conductor as of east to west. Direction of magnetic field at a point above the conductor is
(i) toward north
(ii) toward south
(iii) toward east
(iv) toward west
48. Charged particle moves through a magnetic field perpendicular to it. Energy of particle will
(i) decrease
(ii) increase
(iii) remain unchanged
(iv) become zero
49. In exceeding question, the momentum of particle will
(i) be zero
(ii) change
(iii) not change
(iv) none of above
50. Direct current is sent through a helical spring. Spring tends
(i) to get shorter
(ii) to rotate about the axis
(iii) to get longer
(iv) to move eastward
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