I understand how the problem is solved, the only issue I have is I don't understand how they are getting the units. As in how did they figure out it was kip*ft^3?

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- Nov 28th 2008, 09:22 PMpakmanStrength of materials question (elastic curve)
I understand how the problem is solved, the only issue I have is I don't understand how they are getting the units. As in how did they figure out it was kip*ft^3?

http://img.photobucket.com/albums/v2...ur/elastic.jpg - Nov 29th 2008, 12:33 AMmathwimpSimple - The book's got the units wrong ...
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Simple - The book's got the units...*wrong*

... if it's as simple a "units" problem as it looks.

It happens, typos in manuscripts - or the author had a brain-fart that day; just 'cos it's in print and you might have paid a lot for it (it looks like an expensive book) doesn't mean everything in it is right.

If I understand it, the question's asking for the shape of the curve of the beam. If the "independent" variableis in**x***feet*, then so is- the deflection along any chosen point (presumably) on the curved beam (well, thinking about it a bit,*v**probably*only any chosen point to the left of the ?roller? bearing).

Do you happen to know, as you seem to be in this field, if any*preferably simple*combination of moments/forces applied to a rod will constrain its shape accurately to that of a parabola? I was thinking of working it out "backwards" - working out the (sum of) moment(s)required to produce__that would be__, and in addition trying to use the exact formula for the*y = x²*, ie:*curvature*/**dθ**where*ds*is the angle subtended by element of arc-length*dθ*. Then trying to figure out if any possible (again preferably simple) arrangements of real physical moment(s) can be arranged so as to be equal to the (sum of) moment(s) calculated.*ds*

Toodle pip.

Dennis Revell.

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