Question

The magnetic field produced due to a current-carrying conductor at a point on a distance \( r \) is

• A. directly proportional to \( r \)
• B. directly proportional to \( r^2 \)
• C. inversely proportional to \( r \)
• D. inversely proportional to \( r^2 \)

Hint:

Magnetic field due to a long straight current-carrying wire follows \( B \propto \frac{1}{r} \).

Answer 1

The Correct Option is C

The magnetic field due to a long current-carrying conductor at a distance \( r \) is given by: \[ B = \frac{\mu_0 I}{2 \pi r} \] This indicates that the magnetic field is inversely proportional to the distance \( r \).