Question

A uniform current is flowing along the length of an infinite, straight, thin, hollow cylinder of radius 'R'. The magnetic field 'B' produced at a perpendicular distance 'd' from the axis of the cylinder is plotted in a graph. Which of the following figures looks like the plot?

Options

• 

• 

• 

• 

Answer 1

Explanation:

As magnetic field inside conductor is zero,

For d <R, B = 0

However, for d > R,

`"B" = (mu_0  "I")/(2 pi "d")`

`"i.e.," "B" prop 1/"d"`

Hence, the variation is best depicted by graph (C).