The potential energy of an object is given by U(x)=0.5kx^2+3kx, where U is joules, x is in meters and k is a constant. What is the force acting on the object when x=0?(adsbygoogle = window.adsbygoogle || []).push({});

PE=Fd

0.5kx^2+3kx=Fd

0.5kx+3k=F

F=3k

The answer is -3k, why?

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# Homework Help: Potential energy of an object

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