MCQ
Assertion : If the current in a solenoid is reversed in direction while keeping the same magnitude, the magnetic field energy stored in the solenoid decreases.

Reason : Magnetic field energy density is proportional to square of current.

  • A
    If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
  • B
    If both Assertion and Reason are correct, but Reason is not the correct explanation of  Assertion.
  • C
    If Assertion is correct but Reason is incorrect.
  • If both the Assertion and Reason are incorrect.

Answer

Correct option: D.
If both the Assertion and Reason are incorrect.
d
Reversing the direction of the current reverses the direction of the magnetic field. However, it has no effect on the magneticfield energy density, which is proportional to the square of the magnitude of the magnetic field.

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