Current Electricity and Electrical InstrumentHard
Question
The length of a wire of a potentiometer is 100 cm, and the e.m.f. of its stand and cell is E volt. It is employed to measure the e.m.f. of a battery whose internal resistance is 0.5 Ω. If the balance point is obtained at l = 30 cm from the positive end, the e.m.f. of the battery is
Options
A.
B.
C.
, where I is the current in the potentiometer wire.
, where I is the current in the potentiometer wire.D.
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