A current $i$ flows in a circular coil of radius $r$. If the coil is placed in a uniform magnetic field $B$ with its plane parallel to the field, magnitude of the torque that acts on the coil is
  • A
    Zero
  • B$2\pi \,r\,i\,B$
  • C$\pi \,{r^2}\,i\,B$
  • D$2\pi \,{r^2}\,i\,B$
Medium
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