Biot-Savart law indicates that the moving electrons (velocity `vecv` ) produce a magnetic field `vecB` such that

Options

A. B is perpendicular of
B. B is parallel to V
C. it obeys inverse cube law
D. It is along the line joining the electron and point of observation.

Answer

A

Explanation

In Biot-savart's law, magnetic field `B||dlxxr` and idl due to flow of electron is in opposite direction of v and by direction of cross product of two vectors.
`B vot v`