Question

What can be the cause of helical motion of a charged particle?

Answer 1

Helical motion of charged particle in external magnetic field. When an electron moves in uniform external magnetic field, with velocity not perpendicular, I understand that the magnitude of force is only due to the perpendicular component of velocity and is perpendicular to both components of velocity

Answer 2

Hey !!

Charged particles moves inclined to magnetic field. When there is an angle between velocity of charged particles and magnetic field, then the vertical component of velocity ( v sin θ ) will rotate the charged particles on circular path, but horizontal component ( v cos θ ) will move the charged particle in straight line. Hence path of the charge particle become helical.

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