Multiple choice

A magnetic field in air is measured to be $\overrightarrow{B} = B_0 \bigg(\frac{x}{x^2 + y^2} \hat{y} - \frac{y}{x^2 + y^2} \hat{x}\bigg)$

What current distribution leads to this field? [Hint : The algebra is trivial in cylindrical coordinates.]

  1. $\overrightarrow{J} = \frac{B_0 \hat{z}}{\mu_0} \bigg(\frac{1}{x^2 + y^2}\bigg), r \neq 0$
  2. $\overrightarrow{J} = \frac{B_0 \hat{z}}{\mu_0} \bigg(\frac{2}{x^2 + y^2}\bigg), r \neq 0$
  3. $\overrightarrow{J} = 0\hspace{0.2cm}, r \neq 0$
  4. $\overrightarrow{J} = \frac{B_0 \hat{z}}{\mu_0} \bigg(\frac{1}{x^2 + y^2}\bigg), r \neq 0$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Keep practicing — related questions