A planar coil having 12 turns carries 15 A current. The coil is oriented with respect to the uniform magnetic field vecB=0.2 hati T such that its directed area is vecA=-0.04 hati m 2 . The potential energy of the coil in the given orientation is

Question

A planar coil having 12 turns carries 15 A current. The coil is oriented with respect to the uniform magnetic field vecB=0.2 hati T such that its directed area is vecA=-0.04 hati m 2 . The potential energy of the coil in the given orientation is (A) 0 (B) + 0.72 J (C) +1.44 J (D) -1.44 J

Tardigrade Admin · Accepted Answer

Here, vecB=0.2 hati T ; I=15 A ; N=12 vecA=-0.04 hati m2 Magnetic moment of the coil vecM=N I vecA=(12)(15 A)(-0.04 hati m2) =-7.2 hati A m2 The potential energy of the coil in the given orientation is U=- vecM ⋅ vecB =-(-7.2 hati A m2) ⋅(0.2 hati T) =+1.44 J

Q. A planar coil having 12 turns carries 15A current. The coil is oriented with respect to the uniform magnetic field B=0.2i^T such that its directed area is A=−0.04i^m2 . The potential energy of the coil in the given orientation is

0

+ 0.72 J

+1.44 J

-1.44 J

Here, B=0.2i^T;I=15A;N=12 A=−0.04i^m2 Magnetic moment of the coil M=NIA=(12)(15A)(−0.04i^m2) =−7.2i^Am2 The potential energy of the coil in the given orientation is U=−M⋅B =−(−7.2i^Am2)⋅(0.2i^T) =+1.44J

Q. A planar coil having $12$ turns carries $15 A$ current. The coil is oriented with respect to the uniform magnetic field $B = 0.2 \hat{i} T$ such that its directed area is $A = - 0.04 \hat{i} m^{2}$ . The potential energy of the coil in the given orientation is