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MHT CET202015 Oct 2020Morning ShiftPhysicsCurrent ElectricityActual

The length of potentiometer wire is 4 ~m and is connected in series with an accumulator. The e.m.f. (Unknown) of a cell balances against 1 5 ~m length of wire. If the length of potentiometer wire is doubled, then the new balancing length of wire will be

Options

  1. A4.5 ~m
  2. B1.5 ~m
  3. C0.75 ~m
  4. D3 ~m

Correct answer

D. 3 ~m

Step-by-step solution

If the length is doubled, potential gradient will be half. So to balance the same battery it will take double the length.

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