The period of revolution of a charged particle moving in a uniform magnetic field perpendicular to its velocity is

1. Magnetic force provides centripetal force: qvB = mv²/r. 2. Orbital speed v = qBr/m, so angular velocity ω = v/r = qB/m. 3. Period T = 2π/ω = 2πm/(qB). 4. Notice T is independent of v and r, so the cyclotron frequency stays constant as the particle gains energy. _Source: NCERT Class 12 Physics Ch 4 "Moving Charges and Magnetism", §4.3_