question_answer

The magnetic induction due to an infinitely long straight wire carrying a current i at a distance r from wire is given by                   [MP PET 1994]

A)            \[|B|\,=\left( \frac{{{\mu }_{0}}}{4\pi } \right)\frac{2i}{r}\]              

B)            \[|B|\,=\left( \frac{{{\mu }_{0}}}{4\pi } \right)\frac{r}{2i}\]

C)            \[|B|\,=\left( \frac{4\pi }{{{\mu }_{0}}} \right)\frac{2i}{r}\]              

D)            \[|B|\,=\left( \frac{4\pi }{{{\mu }_{0}}} \right)\frac{r}{2i}\]