Question

Which of the following graph shows the variation of magnetic induction B with distance r from a current carrying long wire?

• A.
• B.
• C.
• D.

Answer 1

Answer: (D)

As magnetic field due to a current carrying straight wire of infinite length
$B=\frac{{\mu }_{0}i}{2\pi }.\frac{1}{r}$
$\Rightarrow B\propto \frac{1}{r}$
So, the graph between magnetic induction $B$ and distance r from the conductor is rectangular hyperbola.