(N/A) The magnetic field lines around a straight current-carrying conductor are concentric circles with the wire as the center. The direction of these lines can be determined using the Right-Hand Thumb Rule.
When the point where the magnetic field is to be determined is moved away from the straight wire,the strength of the magnetic field decreases.
Justification: The magnitude of the magnetic field $(B)$ produced by a straight current-carrying wire at a distance $(r)$ is inversely proportional to the distance from the wire,expressed as $B \propto 1/r$. Therefore,as the distance $(r)$ increases,the magnetic field strength $(B)$ decreases. This can be experimentally verified by observing the deflection of a compass needle,which decreases as it is moved further away from the wire.