A long wire carries a current of 90 A in the east to west direction. What is the magnitude and direction of magnetic field due to the current I.5m below the line?

How are the magnitude and direction of magnetic field at a point denoted by the magnetic lines of force ?

A straight wire is used ot form a semi-circular wire of radius 2cm. IF a current I=10A is passing through the wire,then find the magnitude and direction of magnetic induction at the centre of the semicircle.

Two long parallel straight wires X and Y, separated by a distance of 2.5 cm in air, carry currents of 5 A and 2.5 A respectively in opposite directions. Calculate the magnitude and direction of the force on a 10 cm length of the wire Y.

Two parallel coaxial circular coils of equal radius R and equal number of turns N, carry N carry equal currents I in the same direction and are separated by a distance 2R. Find the magnitude and direction of the magnetic field produced at the mid point of the joining their centres.