作者mkcha (sd)
看板TransPhys
标题[考古] 中原94
时间Tue Jul 4 23:04:32 2006
11.An electron is launched(发射) with velocity v in a uniform magnetic field B
.the angle x between v and B is 0~90.As a result,the electron follows a
helix(螺旋线),its velocity vector v returning to its initial value in a
time interval of
(A)2pmvsinx/eB (B)2pmv/eB (C)2pm/eB (D)2pmvcosx/eB
题目就有点不懂
请问一下答案和所需的观念
谢谢
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1F：→ mkcha:题目应该有错P是别的物理量 被耍了Orz 07/05 02:42