The period of revolution of a charged particle moving in a uniform magnetic field perpendicular to its velocity is
A2πqB/m
BqB/(2πm)
Cm/(2πqB)
D2πm/(qB)
Answer & Solution
Correct answer: D. 2πm/(qB)
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: syllabus Physics Ch 4 "Moving Charges and Magnetism", §4.3_
Keep practising Moving Charges and Magnetism
Browse all Moving Charges and Magnetism questions for AP Intermediate 2nd Year, or explore more Physics topics.
Related questions
The magnetic field at a distance $r$ from a LONG STRAIGHT wire carrying current $I$ isThe magnetic force on a charge $q$ moving with velocity $\vec{v}$ in a magnetic field $\veMatch the magnetism termWork done by a magnetic forceA bismuth bar near a strong magnet on the lab table is:Materials are classified by which quantity?Magnetic field lines of a bar magnet form:The tip of a magnet pointing to geographic north is its: