A positive particle starts at the origin with velocity uî+wk̂ in uniform parallel fields B=Bk̂ and E=Ek̂. With ω=qB/m, which z-coordinate is correct at time t?
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Question

A positive particle starts at the origin with velocity uî+wk̂ in uniform parallel fields B=Bk̂ and E=Ek̂. With ω=qB/m, which z-coordinate is correct at time t?

G1 Physics · Accepted Answer

Motion along B is uniformly accelerated by E, so z=wt+(qE/2m)t². The transverse motion remains circular.