Q142 / 155 · WBJEE 2018 · Physics
A uniform current is flowing along the length dinfinite, straight. thin. hollow cylinder dradius $R$ The magnetic field $B$ produced at perpendicular distance $d$ from the axis of the cylinder is plotied in a graph. Which of the following figures looks like the plot?
- A
- B
- Correct answerC
- D
Solution
$\because$ Magnetic field due to a hollow cylinder of radius $r$
$$
\begin{aligned}
B_{\text {inside }} &=0(\text { for } d < r) \\
B_{\text {outside }} &=\frac{\mu_{0}}{2 \pi} \cdot \frac{i}{d}(\text { for } d \geq r)
\end{aligned}
$$
So, graph between $B$ and $d$.
$$
\begin{aligned}
B_{\text {inside }} &=0(\text { for } d < r) \\
B_{\text {outside }} &=\frac{\mu_{0}}{2 \pi} \cdot \frac{i}{d}(\text { for } d \geq r)
\end{aligned}
$$
So, graph between $B$ and $d$.Hence, the correct answer is option: 'C'.