Why does a moving point charge does not produce a magnetic field? why does it always have to be a current? I am a high-school student with knowledge of basic calculus.
Asked
Active
Viewed 93 times
1 Answers
3
A moving point charge does produce a magnetic field (along with an electric field). After all a current is essentially a collection of moving point charges.
The magnetic field of a point charge moving with a constant velocity $\vec v$ can be approximately determined from Biot-Savart's law or more accurately by Maxwell's equations. In vaccum it is given by: $$\vec B = \frac{\mu_0}{4\pi}.\frac {q \vec v \text{ x } \hat r}{r^2}$$ provided $v \ll c$ ; the speed of light
Hope this helps.
Cross
- 3,360