Category Archives: Maths

Irish Graffiti

Posted on 25/06/2008 by dougaj4

On the 16th October 1843 the Irish mathematician William Hamilton was taking a walk with his wife, alongside the Royal Canal in Dublin, when the answer to a problem that he had been puzzling over came to him, and he … Continue reading →

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The roof of the Taq-i-Kisra; Analysis

Posted on 10/06/2008 by dougaj4

Following the previous post, I have compared the stresses in the Taq-i-Kisra assuming either a catenary or parabolic profile. I have also compared constant depth sections with sections increasing in depth towards the supports. The arch span was taken as … Continue reading →

Posted in Arch structures, Finite Element Analysis, Maths, Newton | Tagged , , , , , | 2 Comments

Elegant Proofs – 1

Posted on 18/05/2008 by dougaj4

Roger Penrose in his book “The Road to Reality” gives a remarkably simple proof of Pythagoras’ Theorem: Drawing a perpendicular to the hypotenuse from the right angle (line CD) will divide any right angled triangle into two similar triangles, both … Continue reading →

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Evaluate Function

Posted on 22/04/2008 by dougaj4

It would often be convenient to evaluate a function entered as text; for instance if we have the function for the deflection of a cantilever under point loading at the end: F*L^3/(3*E*I) then it would be convenient to be able … Continue reading →

Posted in Excel, Maths, UDFs | Tagged , , | 9 Comments

Section Properties of Defined Shapes – Spreadsheet

Posted on 25/03/2008 by dougaj4

Download section properties spreadsheet from: http://www.interactiveds.com.au/software/Section%20Properties03.zip http://www.interactiveds.com.au/software/Section%20Properties07.zip Section properties for 35 defined shapes Section properties from coordinates Section properties UDF Screen shots:

Posted in Excel, Maths, UDFs | Tagged | 29 Comments