Two resistances are joined in parallel whose resultant is $\frac{6}{8}\,ohm$. One of the resistance wire is broken and the effective resistance becomes $2\,\Omega $. Then the resistance in ohm of the wire that got broken was
A$3/5$
B$2$
C$6/5$
D$3$
Medium
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C$6/5$
c If resistances are ${R_1}$ and ${R_2}$ then $\frac{{{R_1}{R_2}}}{{{R_1} + {R_2}}} = \frac{6}{8}$ …..$(i)$
Suppose ${R_2}$ is broken then ${R_1} = 2\, \Omega $ ….. $ (ii)$
On solving equations $(i)$ and $(ii) $ we get ${R_2} = 6/5\,\Omega $
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