$A$ student performs an experiment to study the magnetic effect of current around a current-carrying straight conductor with the help of a magnetic compass.
He reports that:
$(i)$ the degree of deflection of the magnetic compass increases when the compass is moved away from the conductor.
$(ii)$ the degree of deflection of the magnetic compass increases when the current through the conductor is increased.
Which of the above observations of the student appears to be wrong and why?

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(A) The first observation $(i)$ is wrong.
According to the Biot-Savart law or the properties of the magnetic field produced by a straight current-carrying conductor,the magnetic field strength $B$ is inversely proportional to the distance $r$ from the conductor $(B \propto 1/r)$.
Therefore,as the distance from the conductor increases,the strength of the magnetic field decreases.
Consequently,the degree of deflection of the magnetic compass needle should decrease,not increase,as it is moved away from the conductor.

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