The unit vectors $\hat i,\;\hat j\;{\rm{and }}\,\hat k$ are as shown below. What will be the magnetic field at $O$ in the following figure
$\frac{{{\mu _0}}}{{4\pi }}\frac{i}{a}\left( {2 - \frac{\pi }{2}} \right)\,\hat j$
$\frac{{{\mu _0}}}{{4\pi }}\frac{i}{a}\left( {2 + \frac{\pi }{2}} \right)\,\hat j$
$\frac{{{\mu _0}}}{{4\pi }}\frac{i}{a}\left( {2 + \frac{\pi }{2}} \right)\,\hat i$
$\frac{{{\mu _0}}}{{4\pi }}\frac{i}{a}\left( {2 + \frac{\pi }{2}} \right)\,\hat k$
Which of the following statements regarding magnetic lines of force is correct?
Discuss similarities and differences of Biot-Savart law with Coulomb’s law
Unit of magnetic permeability is
The current of $1\,A$ is passed through a hexagonal conducting wire of side $1\,m$ . The magnetic induction at its centre $O$ in $Wb/m^2$ will be
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