# Where can I find spring force problems, with solutions, that involve rectangular coil springs [closed]

Where can I find compression spring force problems and associated solutions that utilize rectangular coil springs?

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 The latest edit actually turned this into a list question, which is not appropriate for this site. I have a strong feeling that there is a good question underlying all of this, but neither this nor the earlier revision makes it clear what that is. – David Zaslavsky♦ Mar 30 '12 at 21:26 Oh, well. Sure do have a lot of "rules" for a Q&A community... Probably lots of Q&A on the "rules." I'll try somewhere else... – user1066701 Mar 30 '12 at 21:37 Yes, of course we have rules. That's not at all unusual for a Q&A site. Everything's explained in the FAQ and on Meta Stack Overflow. (Please keep in mind that all that's happening here is that the question you're asking isn't appropriate for this site in its current form, nothing more.) – David Zaslavsky♦ Mar 30 '12 at 21:47 Rules were ment to be broken. Hell, that IS physics. – user1066701 Apr 9 '12 at 14:06

## closed as off topic by Qmechanic♦, David Zaslavsky♦Mar 30 '12 at 21:22

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If magazine springs are the long soft coiled springs used in gun magazines - exactly what is non-Hookean about them?
I would have thought they would have almost ideal elastic behaviour.

If you have a spring that doesn't obey Hooke's law - eg when the spring is almost fully compressed you would model it as the spring constant being a function of length. Then it's either some calculus or a spreadsheet to calculate it's behaviour

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 You may assume it is an ideal spring (Hookean). Where I'm lost is using the spring equation where there is a variable diameter (coils that are not round). – user1066701 Mar 28 '12 at 19:16

Hooke's law is simply a statement that the force is proportional to the distance, it works nearly without exception (up to small corrections) whenever you can elastically deform a material without changing its shape, heating it up, or making it break. The force you get from your hands is usually not enough to reach the non-linear region of a material, which is close to where you compress it or stretch it enough to do something irreversible, like make defects, or break, or deform. Silly putty bends irreversibly, so it doesn't obey Hooke's law, but metal springs, even irregularly shaped, the rule of thumb is that if you can compress it without bending it permanently, it is going to be linear.

So Hooke's law works without modification.

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 Some miscommunication... Yes, of course the law applies. I was referring more specifically to the need for a spring equation that doesn't assume a fixed outer diameter. – user1066701 Mar 29 '12 at 22:59 @user1066701: There is no such assumption on the shape of the spring, only that the deformations are not plastic. – Ron Maimon Mar 30 '12 at 3:55