An electron moving in a circular orbit of radius $r$ makes $n$ rotations per second. The magnetic field produced at the centre has magnitude
An electron moving in a circular orbit of radius $r$ makes $n$ rotations per second. The magnetic field produced at the centre has magnitude
- [AIPMT 2015]
- A
$\;\frac{{{\mu _0}ne}}{{2\pi r}}$
- B
zero
- C
$\;\frac{{{\mu _0}{n^2}e}}{r}$
- D
$\;\frac{{{\mu _0}ne}}{{2r}}$
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