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The efficiency of a cell when connected ...

The efficiency of a cell when connected to a resistance `R` is `60 %`. What will be its efficiency if the external resistance is increased by six times?

A

0.8

B

0.9

C

0.55

D

0.95

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The correct Answer is:
B
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RESONANCE ENGLISH-CURRENT ELECTRICITY-Exercise-1 (Part-2)
  1. In the figure shown the current flowing 2 R is:

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  2. Find the current through the 10(Omega)resistor shown in figure.

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  3. The efficiency of a cell when connected to a resistance R is 60 %. Wha...

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  4. Two coils connected in series have resistance of 600K Omega and 300 Om...

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  5. Two coils connected in series have resistance of 600K Omega and 300 Om...

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  6. Each resistance shown in the network is in ohm. Current through the re...

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  7. Two electric bulbs marked 25W - 220V and 100W - 220V are connected in ...

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  8. In the figure shown, each resistor is of 20 Omega and the cell has emf...

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  9. Arrange the order of power dissipated in the given circuits, if the sa...

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  10. Five identical resistors each of resistance 1Omega are initially arra...

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  11. Four identical bulbs each rated 100 watt, 220 volts are connected acro...

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  12. Three equal resistors connected in series across a source of EMF...

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  13. The given Wheatstone bridge is showing no deflection in the galvanom...

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  14. Three equal resistances, each of ROmega are connected as shown in figu...

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  15. A wire of resistance 0.1 cm^(-1) bent to form a square ABCD of side 10...

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  16. In the circuit shown in Fig. 7.39, the heat produced in the 5 Omega re...

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  17. A 50 W bulb is in series with a room heater and the combination is con...

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  18. The equivalent resistance between the points A and B is

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  19. A battery of internal resistance 4 Omega is connected to he network of...

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  20. In these circuits all the batteries are indentical and have negllgible...

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