| 1. | A circular coil of radius 4 cm and of 20 turns carries a current of 3 amperes. It is placed in a magnetic field of intensity of 0.5 weber/m². The magnetic dipole moment of the coil is ? | |
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0.6 ampere-m²
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0.45 ampere-m²
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0.15 ampere-m²
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0.3 ampere-m²
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Report Question| 2. | An electron is projected along the axis of a circular conductor carrying the same current. Electron will experience ? | |
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a force perpendicular to the axis.
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a force along the axis.
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no force experienced.
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a force at an angle of 4° with axis.
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| 3. | Which one of the following is correct statement about magnetic forces ? | |
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Inside low magnetic field, magnetic forces obey Newton’s third law.
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Magnetic forces always obey Newton’s third law.
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Magnetic forces do not obey Newton’s third law.
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For very high current, magnetic forces obey Newton’s third law.
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| 4. | A charged particle is moving in a cyclotron, what effect on the radius of path of this charged particle will occur when the frequency of the ratio frequency field is doubled ? | |
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It will be increased by four times.
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It will remain unchanged.
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It will be halved.
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It will also be doubled.
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| 5. | The conversion of a moving coil galvanometer into a voltmeter is done by ? | |
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introducing a resistance of small value in series.
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introducing a resistance of large value in parallel.
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introducing a resistance of large value in series.
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introducing a resistance of small value in parallel.
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| 6. | Which of the following is true ? | |
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Parallel currents repel, and antiparallel currents attract.
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Both parallel and antiparallel currents repel.
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Parallel currents attract, and antiparallel currents repel.
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Both parallel and antiparallel currents attract.
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| 7. | A charge q is moving with a velocity v parallel to a magnetic field B. Force on the charge due to magnetic field is ? | |
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q B/v
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B v/q
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q v B
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zero
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| 8. | A charged particle enters in a uniform magnetic field with a certain velocity. The power delivered to the particle by the magnetic field depends on ? | |
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angular speed w and acceleration of the particle.
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angular speed w and radius r of the circular path.
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force exerted by magnetic field and velocity of the particle.
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None of these
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| 9. | A charged particle moves through a magnetic field perpendicular to its direction. Then ? | |
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both momentum and kinetic energy of the particle are constant
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both momentum and kinetic energy of the particle are not constant
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the momentum changes but the kinetic energy is constant
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kinetic energy changes but the momentum is constant
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| 10. | The magnetic dipole moment of a current loop is independent of ? | |
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area of the loop
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current in the loop
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magnetic field in which it is lying
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number of turns
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