A loop of irregular shape carrying , current is located in an external magnetic field. If the wire is flexible, it change to a circular shape. Why?

What is the magnetic field at the centre C of the circular loop shown in Fig.?

A rectangular coil carrying current is placed in a uniform magnetic field in such a way that normal to the coil makes an angle theta with the direction of magnetic flux density. Find the magnitude of torque acting on the coil Define magnetic moment of a current loop.

Find an expression for the magnetic field at points on the axis of a circular current loop.

Find an expression for the magnetic field at a point on the axis of a circular current loop.