For a bar magnet, the work done in turning from parallel to antiparallel position relative to the field direction is
W=MB(cosθ1−cosθ2), here, θ1=0∘andθ1=180∘.
W=−MBcos180∘(−mBcos0∘)
W=2MB=2×5×0.4=4J
JEE Main 2023 — Physics Electromagnetism
A bar magnet with a magnetic moment 5.0Am2 is placed in parallel position relative to a magnetic field of 0.4T. The amount of required work done in turning the magnet form parallel to antiparallel position relative to the field direction is ________.
Held on 31 Jan 2023 · Verified 6 Jul 2026.
4J
1J
2J
Zero
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