τ=M×B
=IAB
=(0.2)×(43a2)×(2×10−2)=40.2×3×10−2×2×10−2
=3×10−5Nm
JEE Main 2021 — Physics Electromagnetism
A coil in the shape of an equilateral triangle of side 10cm lies in a vertical plane between the pole pieces of permanent magnet producing a horizontal magnetic field 20mT. The torque acting on the coil when a current of 0.2A is passed through it and its plane becomes parallel to the magnetic field will be x×10−5Nm. The value of x is
Held on 26 Aug 2021 · Verified 6 Jul 2026.
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