i have no idea how to do this problem:(adsbygoogle = window.adsbygoogle || []).push({});

a velocity selector consists of electric and magnetic fields described by the expressions E=E(k hat) and B=B(j hat), with B=14.5 mT. Find the vale of E such that a 828-eV electron moving along the positive x axis is undeflected.

hmm..since it is undeflected we can say that qE=qvB, right? and v=E/B...

but how could u solve for E? and how does the 828 eV electron fit into this problem?

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# Homework Help: Magnetic and electric fields

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