Question

Please give a detailed answer about How will the magnetic field intensity at the centre of a circular coil carrying current change,if the current through the coil is doubled and the radius of the coil is halved?

Answer 1

At the center of a current carrying coil, the magnetic field intensity is directly proportional to the current and inversely proportional to the radius of the coil.

So, if the current is doubled and radius is halved, then the value of B increases by 4 times the initial value.