Which one of the following is the CORRECT expression for Biot-Savart law?
1
\(\oint B \cdot dl = {\mu _0}\sum I\)
2
\({\phi _E} = \frac{q}{{{\varepsilon _0}}}\)
3
\(dB \propto \frac{{idl\sin \theta }}{{{r^2}}}\)
4
\(dB = \frac{{i{r^2}\sin \theta }}{{dl}}\)
5
\(dB \propto \frac{{idl\sin \theta }}{{{r^3}}}\)
5
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