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Current Electricity — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity1 Mark
MCQ
A potentiometer wire is 100cm long and a constant potential difference is maintained across it. Two cells are connected in series first to support one another and then in opposite direction. The balance points are obtained at 50cm and 10cm from the positive end of the wire in the two cases. The ratio of emf's is:
  • A
    5 : 1.
  • B
    5 : 4.
  • C
    3 : 4.
  • D
    3 : 2.
✓

Answer

  1. 3 : 2.

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