http://higgs.phys.washington.edu/phy121b/HW/light speed changes.pdf(adsbygoogle = window.adsbygoogle || []).push({});

Above is what I need to do. So essentially, I have to show that in the new reference frame, that the new magnetic force will counter the old electric force. So then I have to use the equation of attraction due to a wire, and then some lorentz contraction. buit then i think i'm lost...Thanks!

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# Current density question

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