In given arrangement $E_1 = 5\, volts$ $E_2 = 7\, volt$ balancing length is $6\,m$ if terminals of $E_2$ are reversed then new balancing length will be
A$1\,m$
B$3\,m$
C$6\,m$
D
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Medium
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D
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d On reversing the cell $\mathrm{E}_{2}$ cbt become
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