21. |
A magnetic needle kept non-parallel to the magnetic field in a non-uniform magnetic field experiences
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Answer:
Option (c) |
22. |
A steamer would like to move in the direction making an angle of 10° south with the west. The magnetic declination at that place is 17° west from the north. The steamer should move in a direction _____ .
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Answer:
Option (a) |
23. |
A toroid wound with 100 turns/m of wire carries a current of 3 A. The core of toroid is made of iron having relative magnetic permeability of μr = 5000 under given conditions. The magnetic field inside the iron is _____ .(Take μ0 = 4π × 10-7 T m A-1)
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Answer:
Option (d) |
24. |
The magnetism of a magnet is due to _____ .
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Answer:
Option (c) |
25. |
A bar magnet is equivalent to a current-carrying _____ .
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Answer:
Option (b) |
26. |
A magnetic wire is bent at its midpoint at an angle of 60°. If the length of the wire is l and its magnetic moment is m, then the magnetic moment of new shape of wire be _____ .
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Answer:
Option (c) |
27. |
If a bar magnet of length 10 cm and pole strength 40 A m is placed at an angle of 30º in a uniform magnetic field of intensity 2 × 10-4T, then torque acting on it is _____ .
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Answer:
Option (c) |
28. |
The horizontal component of Earth's magnetic field at any place is 0.36 × 10-4 Weber/m2. If the angle of dip of that place is 60º, then the value of vertical component of Earth's magnetic field will be _____ (in Wb/m2)
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Answer:
Option (d) |
29. |
At a certain place, the horizontal component of the Earth's magnetic field is B0 and the angle of dip is 60º. The intensity of Earth's magnetic field at that place will be _____ .
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Answer:
Option (b) |
30. |
A magnet makes 30 oscillations per minute at a place where horizontal component of Earth's magnetic field is 0.5 × 10-5 T. At another place, it takes 2.5 s to complete one oscillation. Value of horizontal component of Earth's magnetic field at that place is _____ .
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Answer:
Option (b) |