Question

Current flows through a straight solid cylindrical conductor of radius 'r'. The current is distributed uniformly over its cross-section. The magnetic field at a distance 'x' from the axis of the conductor and normal to it, has magnitude B

• A. B = 0 at the axis
  
• B. $B\propto \frac{1}{x}$ for x>r
  
• C. $B\propto xfor0\le x\le r$
  
• D. B is maximum for x=r

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A

B = 0 at the axis

B

$B\propto \frac{1}{x}$ for x>r

C

$B\propto xfor0\le x\le r$

D

B is maximum for x=r

$B=\frac{{\mu }_{0}ir}{2\pi r^2};r<a=\frac{{\mu }_{0}i}{2\pi r};r>a$