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NEST2021PhysicsCurrent Electricity

A wire of length L and cross-sectional area A has resistance R . It carries a current I when a voltage V is applied to its ends. The wire is melted and drawn to double its length. If the same voltage were to be applied across the wire then

Options

  1. Athe resistance in the wire will be R / 4 .
  2. Bthe resistance in the wire will be 2 R .
  3. Cthe current in the wire will be 2 I .
  4. Dthe current in the wire will be I / 4 .

Correct answer

D. the current in the wire will be I / 4 .

Step-by-step solution

No solution available.

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