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A charged particle moves in a circular trajectory within a magnetic field. The angular velocity is given by ω = qB / m, and the frequency of rotation is v = ω / 2π = qB / 2πm. Which statement about the frequency is accurate?

1. The frequency increases with the charge of the particle.
2. The frequency decreases as the mass of the particle increases.
3. The frequency grows with a stronger magnetic field.
4. The frequency remains unaffected by the charge of the particle.

Correct answer: The frequency decreases as the mass of the particle increases.

Solution

The frequency of rotation is given by v = qB / 2πm. From this equation, it is clear that frequency is directly proportional to charge (q) and magnetic field (B), and inversely proportional to mass (m). Thus, option B is correct.

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