At a point on the exial of a magnet,the magnetic at a induction is found to be 80 `muT`.The induction at a point on its equatorial line at twice the distance of the first point will be

The magnetic induction at a point on equator of a short magnetic dipole is

A straight vertical conductor carries a current. At a point 5cm due north of it, the magnetic induction is founded to be 20muT due east. The magnetic induction at a point 10cm east of its will be

The magnetic induction at a point on axis of a short magnetic dipole is