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The current in a conductor and the poten...

The current in a conductor and the potential difference across its ends are measured by an ammeter and a voltmeter.The meters draw negligible current.The ammeter is accurate but the vlotmeter has a zero error(that is ,it does not read zero when no potential difference is applied).Calculate the zero error if the readings for two different conditions are 1.75A, 14.4Vand 2.75a, 22.4V.

Text Solution

Verified by Experts

Let the voltmeter reading when the
voltmeter has zero error be V
` ((l_1)R/(l_2)R) = (V_1/V_2)`
` rArr (1.75/2.75)=(14.4 -V/22.4 - V)`
` rArr (0.35/0.55)= (14.4-V/22.4-V)`
` 7/11 = (14.4-V/22.4-V)`
` rArr 7 xx (22.4 - V) = 11(14.4 -V)`
` rArr 156.8 - 7V = 158.4 - 11V`
` rArr (7-11) V = 156.8 - 158.4`
` rArr -4V = -1.6`
` rArr V= 0.4 V ` .
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HC VERMA-ELECTRIC CURRENT IN CONDUCTORS-Exercises
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  2. The resistances of an iron wire and a copper wire at 20^(@)Care 3.9(Om...

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  3. The current in a conductor and the potential difference across its end...

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  4. Shown an arrangement to measure the emf (epsilon)and internal resistan...

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  5. The potential dofference between the terminals of a battery of emf6.0V...

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  6. The potential difference between the terminals of a 6.0V battery is 7....

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  7. The internal resistance of an accumulator battery of emf 6V is 10(Omeg...

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  8. Find the value of i(1)//i(2)in figure if (a)R=0.1(Omega) (b)R=1(Ome...

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  9. Consider N=n(1).n(2) identical cells, each of emf (epsilon) and intern...

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  10. A battery of emf 100V and a resistor of resistance 10k(Omega)are joind...

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  11. If the reading of ammeter A(1)in figure is 2.4 A, what will the ammete...

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  12. The resistance of the rheostat shown in figure is 30(Omega). Neglectin...

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  13. Three bulbs,each having a resistance of 180(Omega)are connected in par...

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  14. Suppose you have three resistor of (20 Omega),(50Omega)and (100 Omega)...

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  15. A bulb is made using two filaments.A switch selects whether the filame...

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  16. if a current of 12mA exists in the 5k(Omega) resistor, find the curre...

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  17. An ideal battery sends a current of 5A in a resistor.When another resi...

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  18. Find the equivalent resistances of the network shown in figurebetween ...

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  19. A wire of resistance 15.0(Omega)is bent to form a regular hexagon ABCD...

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  20. Consider the circuit shown in figure.Find the current through the10(Om...

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