| 1. | Electric supply in homes and factories is ? | |
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440V and 220V
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220V and 440V
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400V and 220V
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220V and 400V
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Report Question| 2. | Which of the following statements is incorrect regarding magnetic field lines ? | |
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Relative strength of magnetic field is shown by the degree of closeness of the field lines.
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If magnetic field lines are parallel and equidistant, they represent zero field strength.
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Magnetic field lines are closed curves.
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The direction of magnetic field at a point is taken to be the direction in which the north pole a magnetic compass needle points.
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| 3. | A soft iron bar is introduced inside a current carrying solenoid. The magnetic field inside the solenoid ? | |
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will remain unaffected.
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will decrease.
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will increase.
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will become zero.
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| 4. | Fleming’s left hand and Right hand rules are used in ? | |
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any rule can be used for any device
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both are not applied for generator and motor.
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Generator and electric motor
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Electric motor and generator
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| 5. | Inside the magnet, the field lines moves ? | |
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away from north pole
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away from south pole
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from north to south
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from south the north
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| 6. | Current that does not change its direction after equal intervals of time is called ? | |
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Static electricity
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direct current
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Alternating current
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indirect current
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| 7. | An electric motor is a device which transforms ? | |
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Electrical energy to heat energy only
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Electrical energy to mechanical energy
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Mechanical energy to electrical energy
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Heat energy to electrical only
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| 8. | The magnetic field inside a long straight solenoid carrying current ? | |
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increases as we move towards its end
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is zero
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is the same at all points
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decreases as we move towards its end
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| 9. | An induced current is produced when a magnet is moved into a coil. the magnitude of induced current does not depend on ? | |
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The resistivity of the wire of the coil
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The strength of the magnet
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The number of turns of the coil
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The speed with which the magnet is moved
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| 10. | Each one of the following changes will increase emf (or voltage) in a simple generator except ? | |
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Increasing the speed of rotation
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Increasing the size of the gap in which the armature turns
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Winding the coil on a soft iron armature
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Increasing the number of turns in the armature coil
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