| 1. | The materials are a bit inferior conductors of magnetic flux than air ? | |
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ferromagnetic
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paramagnetic
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diamagnetic
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dielectric
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Report Question| 2. | The magnetic materials exhibit the property of magnetisation because of ? | |
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orbital motion of electrons
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spin of electrons
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spin of nucleus
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all of the above
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| 3. | A permanent magnet ? | |
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attracts some substances and repels others
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attracts all paramagnetic substances and repels others
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attracts only ferromagnetic substances
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attracts ferromagnetic substances and repels all others
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| 4. | The magneto-motive force is ? | |
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the voltage across the two ends of exciting coil
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the flow of an electric current
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the sum of all currents embraced by one line of magnetic field
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the passage of magnetic field through an exciting coil
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| 5. | Materials subjected to rapid reversal of magnetism should have ? | |
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large area of B-H loop
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high permeability and low hysteresis loss
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high coercivity and high retentivity
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high coercivity and low density
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| 6. | Which of the following materials are diamagnetic ? | |
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Silver
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Copper
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Silver and copper
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Iron
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| 7. | The change of cross-sectional area of conductor in magnetic field will affect ? | |
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reluctance of conductor
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resistance of conductor
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(a) and (b) both in the same way
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none of the above
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| 8. | The working of a meter is based on the use of a permanent magnet. In order to protect the meter functioning from stray magnetic fields ? | |
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meter is surrounded by strong magnetic fields
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a soft iron shielding is used
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a plastic shielding is provided
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a shielding of a non-magnetic material is used
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| 9. | A permeable substance is one ? | |
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which is a good conductor
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which is a bad conductor
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which is a strong magnet
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through which the magnetic lines of force can pass very easily
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| 10. | What will be the current passing through the ring shaped air cored coil when number of turns is 800 and ampere turns are 3200 ? | |
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2
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4
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6
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8
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