Assertion : If the current in a solenoid is reversed in direction while keeping the same magnitude, the magnetic field energy stored in the solenoid remains unchanged.
Reason : Magnetic field energy density is proportional to the magnetic field.
AIIMS 2010,AIIMS 2017, Easy
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Reversing the direction of the current reverses the direction of the magnetic field. However, it has no effect on the magnetic field energy density, which is proportional to the square of the magnitude of the magnetic field.
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