Discuss the magnetic field resulting from a current carrying circular ring.

In a case of a current carrying circular ring, we first divide the ring into various small parts and then we will see contribution of each part.

•First consider the leftmost part which have a magnetic field which is coming out of the paper i.e. perpendicular to the paper.

•Similarly, when we consider the rightmost part whose magnetic field is also coming out of the paper and also perpendicular to the paper.

•So, while coming from left to right all the parts will contribute their magnetic fields similarly. And the resultant magnetic field at the centre of the ring is coming out of the paper and perpendicular to the paper.

(The resultant magnetic field of the ring.)

Now it is obvious that the ring lines are circular near the wire but when we come away from the wire they change and they nearly convert into straight lines near the centre of the ring because the radius of the magnetic circle increase as we move towards the centre of the ring which result into the straight light of magnetic field lines.