A current of two amperes is flowing through a cell of $e.m.f.$ $5\, volts$ and internal resistance $0.5\, ohm$ from negative to positive electrode. If the potential of negative electrode is $10\,V$, the potential of positive electrode will be .............. $V$
A$5$
B$14 $
C$15$
D$16$
Medium
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B$14 $
b ${V_2} - {V_1} = E - ir = 5 - 2 \times 0.5 = 4\,volt$
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