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Two cells of the same e.mf. e but differ...

Two cells of the same e.mf. e but different internal resistances `r_(1) and r_(2)` are connected in series with an external resistance 'R'. The potential drop across the first cell is found to be zero. The external resistance Ris

A

`sqrt(r_1 r_2)`

B

`r_1 +r_2`

C

`r_1 -r_2`

D

`(r_1 +r_2)/( 2)`

Text Solution

Verified by Experts

The correct Answer is:
C
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AAKASH SERIES-APPENDICES ( REVISION EXERCISE )-REVISION EXERCISE (CUTTENT ELECTRICITY )
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  7. A 5V battery with internal resistance 2 Omega and a 2V battary with i...

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  10. For a cell, the graph between the p.d.(V) across the terminals of the ...

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  15. The P.d between the terminals A&B is

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  18. In the circuit shown, current (in A) through the 50 V and 30V batterie...

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