| 1. | When electric current passes through a metallic conductor, its temperature rises. This is due to ? | |
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collisions between conduction electrons and atoms
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the release of conduction electrons from parent atoms
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mutual collisions between metal atoms
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mutual collisions between conducting electrons
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Report Question| 2. | Whether circuit may be AC. or D.C. one, following is most effective in reducing the magnitude of the current ? | |
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Reactor
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Capacitor
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Inductor
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Resistor
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| 3. | The minimum charge on an ion is ? | |
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equal to the atomic number of the atom
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equal to the charge of an electron
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equal to the charge of the number of electrons in an atom
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zero
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| 4. | A field of force can exist only between ? | |
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two molecules
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two ions
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two atoms
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two metal particles
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| 5. | A substance whose molecules consist dissimilar atoms is called ? | |
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semi-conductor
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super-conductor
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compound
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insulator
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| 6. | An electric filament bulb can be worked from ? | |
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D.C. supply only
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A.C. supply only
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Battery supply only
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All above
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| 7. | An open resistor, when checked with an ohm-meter reads ? | |
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zero
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infinite
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high but within tolerance
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low but not zero
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| 8. | When resistance element of a heater fuses and then we reconnect it after removing a portion of it, the power of the heater will ? | |
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decrease
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increase
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remain constant
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none of the above
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| 9. | Heat in a conductor is produced on the passage of electric current due to ? | |
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reactance
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capacitance
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impedance
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resistance
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| 10. | Resistance of a material always decreases if ? | |
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temperature of material is decreased
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temperature of material is increased
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number of free electrons available become more
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none of the above is correct
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