Question

The magnetic field at the origin due to a current element $\overrightarrow{id1}$ placed at a point with vector position $\overrightarrow{r}$ is

• A. $\frac{{\mu }_{0}i}{4\pi }\frac{\overrightarrow{d1}\times \overrightarrow{r}}{r^3}$
• B. $\frac{{\mu }_{0}i}{4\pi }\frac{\overrightarrow{r}\times \overrightarrow{d1}}{r^3}$
• C. $\frac{{\mu }_{0}i}{4\pi }\frac{\overrightarrow{d1}\times \overrightarrow{r}}{r^2}$
• D. $\frac{{\mu }_{0}i}{4\pi }\frac{\overrightarrow{r}\times \overrightarrow{d1}}{r^2}$

Answer 1

Answer: (A)

$\frac{{\mu }_{0}i}{4\pi }\frac{\overrightarrow{dl}\times \vec{r}}{r^3}$