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MHT CET202121 Sep 2021Morning ShiftPhysicsMagnetic Effects of CurrentActual

A long solenoid carrying a current produces a magnetic field B along its axis. If the number of turns per cm is doubled and the current is made, ( 1 3 )^ rd then the new value of the magnetic field will be

Options

  1. AB 3
  2. B3 ~B
  3. C2 ~B
  4. D2 ~B 3

Correct answer

D. 2 ~B 3

Step-by-step solution

Magnetic field inside a solenoid is given by B = ₀ nI If n is doubled and I is made ( 1 3 )^ rd , the value of B will become 2 3 ~B

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