Consider a circular current carrying conducting coil.
What is the ratio of the magnetic fields at the centre of a circular coil carrying current to that at a point whose distance is half of the radius of the coil ?
Answer & explanation
Correct answer: option 3
magnetic field at the centre of a circular coil carrying current I, Bc = μoI/2R
magnetic field at a point whose distance is half of the radius of the coil (R/2) ,
Bz = μoI/(R2 + (R/2)2)3/2
Ratio = Bc/Bz = (5/4)3/2