The magnetic field produced by a current-carrying straight wire at a p

The magnetic field produced by a current-carrying straight wire at a point outside the wire depends

[amp_mcq option1=”inversely on the distance from it” option2=”directly on the distance from it” option3=”inversely at short distances and directly at large distances from it” option4=”directly on the distance (at short distances) and inversely on the distance (at long distances) from it” correct=”option1″]

This question was previously asked in

UPSC NDA-1 – 2022

Download PDF Attempt Online

The magnetic field produced by a current-carrying straight wire at a point outside the wire depends inversely on the distance from it.

The magnitude of the magnetic field ($B$) at a distance ($r$) from a long, straight conductor carrying current ($I$) is given by the formula $B = \frac{\mu_0 I}{2\pi r}$, where $\mu_0$ is the permeability of free space.

From the formula $B = \frac{\mu_0 I}{2\pi r}$, it is clear that for a constant current $I$, the magnetic field strength $B$ is inversely proportional to the distance $r$ from the wire ($B \propto \frac{1}{r}$). This relationship holds true for points outside the wire.

More similar MCQ questions for Exam preparation:-