| 1. | The internal resistance of dry cell is ........ than the internal resistance of common electrolytic cell. ? | |
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slightly higher
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slightly lower
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much lower
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much higher
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Report Question| 2. | In meter bridge or Wheatstone bridge for measurement of resistance, the known and the unknown resistance are interchanged. The error so removed is ? | |
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index error
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due to temperature effect
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end correction
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random error
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| 3. | In a potentiometer of 10 wires, the balance point is obtained on the 7th wire. To shift the balance point to 9th wire, we should ? | |
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increase resistance in series with the cell whose emf is to be determined.
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decrease resistance in series with the cell whose emf is to be measured.
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increase resistance in the main circuit.
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decrease resistance in the main circuit.
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| 4. | Which of the following characteristics of electrons determines the current in a conductor ? | |
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Thermal velocity alone
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Drift velocity alone
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Both drift velocity and thermal velocity
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Neither drift nor thermal velocity
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| 5. | The electric resistance of a certain wire of iron is R. If its length and radius are both doubled, then ? | |
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the resistance will be halved and the specific resistance will be doubled
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the resistance will be halved and the specific resistance will remain unchanged
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the resistance will be doubled and the specific resistance will be halved
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the resistance and the specific resistance, will both remain unchanged
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| 6. | Nichrome or Manganin is widely used in wire bound standard resistors because of their ? | |
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temperature independent resistivity
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very weak temperature dependent resistivity
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strong dependence of resistivity with temperature
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mechanical strength
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| 7. | To minimise the power loss in the transmission cables connecting the power stations to homes and factories, the transmission cables carry current ? | |
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at a very low voltage
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neither at a very high voltage nor at a very low voltage
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at a very high voltage
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at 220 volt
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| 8. | Sensitivity of potentiometer can be increased by ? | |
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increasing the length of the potentiometer
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decreasing the length of the potentiometer wire
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increasing the e.m.f of the cell
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None of these
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| 9. | Why is the Wheatstone bridge better than the other methods of measuring resistances ? | |
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It has four resistor arms
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It is a null method
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It is based on Kirchoff’s law
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It does not involve Ohm’s law
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| 10. | A potentiometer is an accurate and versatile device to make electrical measurements of E.M.F. because the method involves ? | |
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A condition of no current flow through the galvanometer
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Cells
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Potential gradients
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A combination of cells, galvanometer and resistances
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