Different shapes of conductors have different type of magnetic field.

•Take a straight thick copper wire and place it between the points X and Y in an electric circuit. The wire XY is kept perpendicular to the plane of the paper.

• Horizontally place a small compass near this copper wire. See the position of its needle.

• Pass the current through the circuit by inserting the key into the plug.

• Observe the change in the position of the compass needle and the direction of deflection.

•Interchange the battery connection in the circuit so that the direction of the current in the copper wire changes.

• Observe the change in the direction of deflection of the needle.