Question

A particle carrying a charge to $100$ times the charge on an electron is rotating per second in a circular path of radius $0.8\, m$. The value of the magnetic field produced at the centre will be
( $\mu _0=$ permeability for vacuum)

• A. $\frac{10^{-7}}{\mu_{0}}$
• B. $10^{-17}\,\mu_0$
• C. $10^{-6}\,\mu_0$
• D. $10^{-7}\,\mu_0$

Answer 1

Answer: (B)

Current, $i=\frac{q}{t}=100\times e$
$B_{centre}=\frac{\mu_{0}}{4\pi}. \frac{2\pi i}{r}$
$=\frac{\mu_{0}}{4\pi}. \frac{2\pi\times100e}{e}$
$\frac{\mu_{0}\times200\times1.6\times10^{-19}}{4\times0.8}$
$=10^{-17}\,\mu_{0}$