An electron is moving in a cyclotron at a speed of `3.2 xx 10^(7) m s^(-1)` in a magnetic field of `5 xx 10^(-4) T` perpendicular to it. What is the frequency of this electron? `(q=1.6xx10^(-19)C, m_(c)=9.1xx10^(-31)kg)`

Options

A. `1.4xx10^(5)Hz`
B. `1.4xx10^(7)Hz`
C. `1.4xx10^(6)Hz`
D. `1.4xx10^(9)Hz`

Answer

B

Explanation

`v=3.2xx10^(7)"m s"^(-1),B=5xx10^(-4)T`
The frequency of electron is
`upsilon =(qB)/(2pim)=(1.6xx10^(-19)xx5xx10^(-4))/(2xx3.14xx9.1xx10^(-31))`
`upsilon=1.4xx10^(7)" Hz = 14 MHz"`