Two wires `A` and `B` are of lengths `40cm` and `30cm`. A is bent into a circle of radius `r` and `B` into an arc of radius `r`. A current `i_(1)` is passed through `A` and `i_(20)` through `B`. To have the same magnetic inductions at the centre, the ratio of `i_(1):i_(2)` is

A circular coil of average radius 6 cm has 20 turns. A current 1.0 A is set up through it. Find the magnetic induction at (i) The centre of the coil

A wire of length 10cm is bent into an arc of a circle such that it subtends an angle of 1 radian at the centre. If a current of 1A is passed through the wire, the magnetic induction at the centre of the circle will be

Two identical wires A and B have the same length l and carry the same current I. Wire A is bent into a circle of radius R and wire B is bent to form a square of side a. If B_1 and B_2 are the values of magnetic induction at the centre of the circle and the centre of the square, respectively, then the ratio B_1//B_2 is

A wire of length 'L' is bent in to an arc of a circle and found to subtentd and angle of 'theta' radians at the centre.If a current of 'I' is passed through it, the magnetic induction at the center of the circle is

A wire of length l, carrying current i, is bent in circle of radius r, then magnetic momennt at centre of loop is

A wire of length L is shaped into a circle and then folded as shown. Magnetic moment of the frame when a current i is passed through it is:

Two identical wires A and B , each of length 'l', carry the same current I . Wire A is bent into a circle of radius R and wire B is bent to form a square of side 'a' . If B_(A) and B_(B) are the values of magnetic field at the centres of the circle and square respectively , then the ratio (B_(A))/(B_(B)) is :

A circular arc of wire of radius of curvature r subtends an angle of p/4 radian at its centre. If i current is flowing in it then the magnetic induction at its centre is -

If a straight conductor of length 40cm bent in the form of a square and the current 2A is allowed to pass through square, then find the magnetic induction at the centre of the square loop.