Force Acting on Moving Charges: Practice Problem & Solution

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:

Center field is $B = \frac{\mu_0 I}{2R}$ with $I = \frac{ev}{2\pi R}$, giving $B = \frac{\mu_0 ev}{4\pi R^2}$. Thus, radius $R$ is proportional to $\sqrt{v/B}$.