Question

Following charge has maximum frequency of rotation in uniform transverse magnetic field :-

• A. a proton
• B. an alpha particle
• C. an electron
• D. a neutron

Answer 1

Answer: (C)

$\omega =\frac{qB}{m}$
$\Rightarrow so,v\propto \frac{q}{m}$
for proton $\frac{q}{m}=\frac{e}{m_p}$
for alpha particle $\frac{q}{m}=\frac{2e}{4m_p}=\frac{e}{2m_p}$
for $e^{-}\frac{q}{m}=\frac{e}{m_e}$
Therefore $e^{-}$has highest $\frac{q}{m}$ ratio.
So, its frequency of revolution will be highest.