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PhysicsJEE Main 21 Jan 2026, Shift 2·Q17·MCQ·Moderate

Moving Charges and Magnetism · Sources of magnetic field

An infinitely long straight wire carrying current I is bent in a planar shape as shown in the diagram. The radius of the circular part is r. The magnetic field at the centre O of the circular loop is :
  1. (1)μ02πIr(π+1) i^\dfrac{\mu_0}{2\pi}\dfrac{I}{r}(\pi + 1)\,\hat i
  2. (2)−μ02πIr(π−1) i^-\dfrac{\mu_0}{2\pi}\dfrac{I}{r}(\pi - 1)\,\hat i
  3. (3)μ02πIr(π−1) i^\dfrac{\mu_0}{2\pi}\dfrac{I}{r}(\pi - 1)\,\hat i
  4. (4)−μ02πIr(π+1) i^-\dfrac{\mu_0}{2\pi}\dfrac{I}{r}(\pi + 1)\,\hat i
We corrected a printing error in the original paper

Source printed “planer”.

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