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NEET2024PhysicsCurrent ElectricityActual

A uniform wire of diameter d carries a current of 100 mA when the mean drift velocity of electrons in the wire is v . For a wire of diameter d 2 of the same material to carry a current of 200 mA , the mean drift velocity of electrons in the wire is

Options

  1. A4 v
  2. B8 v
  3. Cv
  4. D2 v

Correct answer

B. 8 v

Step-by-step solution

current i=n A v_d e ( v_d= mean drift velocity )=n ( D^2 4 ) v_d e i D^2 v_d 100 200 = (d)^2 ( d 2 )^2 v v^ v^ =2 2^2 v=8 v

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