(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

In a velocity selector E and B fields are perpendicular. Which of the following conditions on the direction of the particle's velocity can result in no net force assuming the E and B are nonzero?

2. Relevant equations

F = Eq + q(vxB)

3. The attempt at a solution

The answer is B.

A) v is parallel to E

--Not sure why this wouldn't work. Since E is perpendicular to B why can't it result in F = 0? F = E + vB

B) v is parallel to (ExB)

--If I recall my cross product information correctly. v will be perpendicular to both E and B therefore I get F = E + vB.

What's the difference between the two?

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# Homework Help: Lorentz Force

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