W=PE(cosθ1−cosθ2)
W=PE(cos0−cos60o)
=2PE.
⇒PE=2W
τ=PEsinθ=2Wsin60o=3W.
A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in equilibrium state. The energy required to rotate it by 60o is W. Now, the torque required to keep the magnet in this new position is
Held on 30 Apr 2016 · Verified 9 Jul 2026.
3W
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32W
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