A charged particle of charge q and mass m enters perpendicularly

A charged particle of charge q and mass m enters perpendicularly in a magnetic field . Kinetic energy of the particle is E; then frequency of rotation is

For circular path in magnetic field, mrω² = qvB

⇒ ω² =	qvB	As v = rω
	mr

∴ ω² =	q(rω)B	⇒ ω =	qB
	mr		m

∴ If ν is frequency of roatation, then

v =	ω	⇒ v =	qB
	2π		2πm