Motion of a Charged Particle in Electric & Magnetic Fields

AI Thread Summary
The discussion centers on analyzing the motion of a charged particle initially at rest in a constant uniform magnetic field while subjected to an oscillating electric field. The Lorentz force law is applied to derive the equations of motion, incorporating both the electric and magnetic fields, which are perpendicular to each other. The participant mentions considering damping and resisting forces in the oscillatory motion, leading to an analytical solution that shows oscillatory behavior in the xz plane. The damping factor is noted to eventually bring the particle to rest as time approaches infinity. Full details of the problem are encouraged for further clarification and validation of the solution.
BishwasG
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I can't figure out what is the motion of a charged particle at rest at origin in a constant uniform magnetic field when it is subjected to an oscillating electric field starting t = 0. I need to find the equations representing its motion.
 
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Use the Lorentz force law\mathbf{F}=q(\mathbf{E}+\mathbf{v} \times \mathbf{B}) where F is the force, q is the charge, E is the electric field and B is the magnetic field. Then, you substitute the resulting expression into Newton's Second Law, \mathbf{F}=m\mathbf{a}. Then you just plug and chug and solve the resulting Diff. Eq. (You didn't specify the directions of the E and B fields, so I can't go any further. xP)

Hope that helps!
 


E and B fields are perpendicular. I have to take into account the damping and resisting forces for the oscillatory motion. I need to find a solution analytically for the motion of the particle in that case. I managed to do it, but I am not sure if I did it right. If the B field is along y-axis and E along x, I found an oscillatory motion in xz plane. The damping factor brings it to rest as time goes to infinity.
 


You should post the full details of the problem.
 
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