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AP EAMCET202125 Aug 2021Evening ShiftPhysicsCurrent ElectricityActual

The null point of a potentiometer with a cell of emf is obtained at a distance l on the wire, then

Options

  1. Al
  2. Bl^2
  3. C1 l
  4. D1 l^2

Correct answer

A. l

Step-by-step solution

As we know, electric field, E=- d V d r Hence, emf is also directly proportional to l i.e., l .

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