consider a long straight wire of cross section area A carrying a curent i. let there be n free electrons per unit volume , an observer sitting in the car moving in thw same direction with a speed of v=i/nAe and seperated from the wire by a distance r. the magnetic field seen by the observer is ???

Answers (1)

The observer's relative velocity with respect to the electron is 0.

the magnetic field as seen by the observer is very nearly to \frac{\mu_0 i}{2pr}