A current `'I'` flows along an infinitely long straight conductor. If `'r'` is the perpendicular distance of a point from the lower end of the conductor, then the magnetic induction `B` is given by

A current 'I' flows along an infinitely long straight conductor. If r is the perpendicular distance of a point, very far from the ends of the conductor then the magnetic induction B is given by

A current I ampere flows along an infinitely long straight thin walled tube, then the magnetic induction at any point inside the tube is .

A current of IA, flows along an infinitely long Staight thin walled tube. The magnetic induction at any point inside the tube is

Magnetic field at a distance r from an infinitely long straight conductor carrying steady varies as

A current i is flowing in a straight conductor of length L. The magnetic induction at a point distant L/4 from its centre will be-

A current i is flowing in a straight conductor of length L. The magnetic induction at a point distant L/4 from its centre will be-

A current i is flowing in a straight conductor of length L. The magnetic induction at a point distant L/4 from its centre will be-

An infinitely long straight conductor carries a current of 100A . At what distance from the conductor is the magnetic field caused by the current equal to 0.5xx10^-4T ?

A current i ampere flows along the inner conductor of a coaxial cable and returns along the outer conductor fo the cable, then the magnetic induction at any point outside the conductor at a distance r metre from the axis is