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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

Text Solution

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The correct Answer is:
B
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RESONANCE-CURRENT ELECTRICITY-Exercise-1 (Part-2)
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  2. Find the current through the 10(Omega)resistor shown in figure.

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

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  12. The current i in the circuit (see figure) is

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  15. Three equal resistace, each of R ohm, are connectedd as shown in the f...

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  17. In the circuit shown in Fig.6.2, the heat produced in 5Omega resistor,...

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

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  19. The equivalent resistance between the points A and B is:

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  20. A battery of internal resistance 4Omega is connected to the network of...

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