When you drop a (strong) magnet into a copper pipe, it slows down. Is there an equation for calculating the force? I have searched and searched Google, but all i found was F=[(B^2)(l^2)v]/R, where B = magnetic field, l = circumference of tube, v = velocity of magnet, and R = resistance of pipe. I have plugged numbers in, but it does not seem to be reasonable!(adsbygoogle = window.adsbygoogle || []).push({});

I got the equation from: http://www.du.edu/~jcalvert/phys/eddy.htm

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# Eddy current pipe force equation

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