The magnetic field at the centre of square of side a is

Find the magnetic field at the centre P of square of side a shown in .

Find the magnetic field at the centre of a square of side 'a' carrying current IA.

The ratio of the magnetic field at the centre of a current carrying circular wire and the magnetic field at the centre of a square coil made from the same length of wire will be

A square loop of side a carris a current I . The magnetic field at the centre of the loop is