Question

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

• A. A
• B. B
• C. C
• D. D

Answer 1

The correct option is C C

For the magnetic field$\overrightarrow{B}$ at P due to current I in wire AB when P is a distance from wire is

$\overrightarrow{B}=\frac{{\mu }_0}{4\pi }\left(\frac{I}{r}\right)$ and

$\overrightarrow{B}\propto \frac{1}{r}$

Thus C.