| 1. | Current I is flowing in a coil of area A and number of turns is N, then magnetic moment of the coil in M equal to ? | |
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NI/A
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NIA
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NI/ A
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N^2 AI
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Report Question| 2. | A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It will ? | |
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become rigid showing no movement
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stay in any position
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stay in east-west direction only
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stay in north-south direction only
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| 3. | One can define ........ of a place as the vertical plane which passes through the imaginary line joining the magnetic North and the South–poles. ? | |
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magnetic inclination
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magnetic declination
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magnetic meridian
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geographic meridian
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| 4. | Which of the following independent quantities is not used to specify the earth’s magnetic field ? | |
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Magnetic dip
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Magnetic declination
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Vertical component of earth’s field (BV).
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Horizontal component of earth’s field (BH).
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| 5. | The material suitable for making electromagnets should have ? | |
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low retentivity and low coercivity.
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high retentivity and low coercivity.
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high retentivity and high coercivity.
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low retentivity and high coercivity.
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| 6. | S is the surface of a lump of magnetic material. ? | |
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Some lines of B must be discontinuous across S.
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Lines of H are necessarily continuous across S.
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Lines of H cannot all be continuous across S.
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Lines of B are not necessarily continuous across S.
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| 7. | In a permanent magnet at room temperature ? | |
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the individual molecules have non-zero magnetic moment which are all perfectly aligned.
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domains are all perfectly aligned.
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magnetic moment of each molecule is zero.
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domains are partially aligned.
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| 8. | Let the magnetic field on earth be modelled by that of a point magnetic dipole at the centre of earth. The angle of dip at a point on the geographical equator ? | |
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cannot be positive or negative.
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is not bounded.
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can be zero at specific points.
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is always zero.
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