Need help with graphs of potential energy and force

AI Thread Summary
The discussion focuses on the potential energy function U(x) and its corresponding force function F(x) for a point mass. The user successfully graphed U(x) but struggles with F(x), having derived its formula but unable to visualize it. Participants suggest that understanding the relationship between U(x) and F(x) can help in sketching F(x) without a plotting tool. They emphasize the importance of analyzing U(x) for asymptotic behavior and key features to infer the characteristics of F(x). The conversation highlights the need for a deeper understanding of the mathematical relationships involved in graphing these functions.
Spyridoula
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Hi everyone!

Homework Statement



The potential energy U of a point mass is U(x)= Uoxo x/(x2 + xo2) where Uo and xo are positive contants, Uo in joule and x,xo in meters. Draw the graphs of U(x) and F(x).

Homework Equations



F(x) = -dU/dx

The Attempt at a Solution



I found the F(x) function and made the U(x) graph but I'm stuck with the F(x) graph and I'm not totally sure for anything that I found so far.

Thank you!
 
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Please post what you got for the F(x) function. For the graphs, either post your attempts or at least a verbal description.
 
For the F(x) I found that it is V0x0 (x+x0)(x-x0) / (x2 + x02)2

I can't make a graph out of it. As for the U(x) the graph is in the attachment below.
U(x)=0 when x=0 and Vmax=V0/2 when x=x0
 

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  • MSP341911a40ca99741cac38000060i1bef752e64i66.gif
    MSP341911a40ca99741cac38000060i1bef752e64i66.gif
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When sketching a graph, you should take it far enough to illustrate asymptotic behaviour. What is that for U(x)?
I don't understand why cannot get a graph for F. What tool did you use to get the graph for U? You ought to be able to sketch graphs from the formula without using a plotting tool. That's how you know which sections are interesting to plot.
Can you at least describe in words what F(x) would look like by inspection of the U(x) graph? Say what the asymptotic values are, over what ranges it would be positive, where the zeroes are, and all extrema.
 
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