Physic Labs

Problem 2

A particle of mass mm and charge qq moves perpendicular to a uniform magnetic field BB at speed vv. Find orbit radius and period; use ∣q∣|q| for charge magnitude. The magnetic field is perpendicular to the initial velocity; neglect gravity and collisions. (a) Use the Lorentz force to find orbit radius rr. (b) Find the orbital period TT. (c) Find the cyclotron frequency and identify which result is independent of speed vv. Express each answer in terms of the supplied parameters, using SI units for any numerical evaluation. State the assumptions used, check dimensions at each result, and compare with the governing law to catch a sign error or a missing condition.
FB=∣q∣vBF_B=|q|vB
problems.proof.analysis

First isolate the parts of the system linked by the stated constraint and choose the governing law; this puts the quantities under a consistent convention. The idealizations exclude interactions not included in the model.

problems.proof.pitfall. Do not omit the sign convention or the model’s physical condition; check the limiting case before accepting a solution.