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Manipal MET2016PhysicsCurrent Electricity

In a potentiometer experiment for measuring the emf of a cell, the null point is at 240 cm when we have a 500 resistor in series with the cell and galvanometer. If the series resistance reduced to half, then the null point will be at

Options

  1. A480 cm
  2. B240 cm
  3. C120 cm
  4. D60 cm

Correct answer

B. 240 cm

Step-by-step solution

The resistance in series with galvanometer does not affect the null point. So, it will obtained at 240 cm .

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