An electron moving in a circular orbit of radius `r` makes `n` rotation per secound. The magnetic field produced at the centre has magnitude

Options

A. zero
B. `(mu_(0)n^(2)e)/(r)`
C. `(mu_(0)n e)/(2r)`
D. `(mu_(0)n e)/(2pir)`

Answer

C

Explanation

Current `i=q/T=e/((2pi)/(omega))=e/((2pi)/(2pin))=em`
`B=(mu_(0)i)/(2r)=(mu_(0)en)/(2r)`