On What factors the magnetic induction at the centre of the coil depends?

The electric current in a circular coil of two turns produced a magnetic induction of 0.2 T at its centre. The coil is unwound and then rewound into a circular coil of four turns. If same current flows in the coil, the magnetic induction at the centre of the coil now is

The electric current in a circular coil of two turns produced a magnetic induction of 0.2 T at its centre. The coil is unwound and then rewound into a circular coil of four turns. If same current flows in the coil, the magnetic induction at the centre of the coil now is

The electric current in a circular coil of two turns produced a magnetic induction of 0.2 T at its centre. The coil is unwound and then rewound into a circular coil of four turns. If same current flows in the coil, the magnetic induction at the centre of the coil now is

The current through a circular coil appears to be flowing in clock-wise direction for an observer. The magnetic induction at the centre of the coil is:

The current through a circular coil appears to be flowing in clock-wise direction for an observer. The magnetic induction at the centre of the coil is:

A direct current is passing through a wire. It is bent to form a coil of one turn. Now it is further bent to form a coil of two turns but at smaller radius. The ratio of the magnetic induction at the centre of this coils and at the centre of the coil of two turn is

A coil of self inductance 20 mH, having 50 turns, carries a current of 300 mA. If the area of the coil is 2cm^(2) , the magnetic induction at the centre of the coil is