Rankers Physics

Force Acting on Moving Charges: Practice Problem & Solution

An electron having mass '$m$' and kinetic energy E enter in uniform magnetic field B perpendicularly, then its frequency will be: (2001)
$\frac{eE}{qVB}$
$\frac{2\pi m}{eB}$
$\frac{eB}{2\pi m}$
$\frac{2m}{eBE}$

Solution Explained:

To solve this problem, we apply the core principles of Force Acting on Moving Charges. Understanding the underlying formula is key to arriving at the correct answer below:

Cyclotron frequency is given by $f = \frac{qB}{2\pi m}$. For an electron, the charge is $e$, yielding $\frac{eB}{2\pi m}$.

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