How Do You Apply Lagrange Multipliers to a Rolling Disk and Fixed Bar System?

deniz120
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Homework Statement



Hi all, I need to derive differantial equations of system with lagrange multiplier method, a disk is rolling and a bar is fixed onto the point of a disk

[PLAIN]http://img130.imageshack.us/img130/1669/adsziss.jpg
By deniz120 at 2010-05-31


Homework Equations





The Attempt at a Solution


please check my solution below, I derived T and V for Lagrange, all I need is help for constaints, lagrange multiplier equation. Thanks in advance:)

[PLAIN]http://img263.imageshack.us/img263/3659/tarama0001r.jpg
By deniz120 at 2010-05-31]
 
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unfortunately nothing, I guess there is nonholonomic constraint
thanks
 
It's not a nonholonomic constraint.

You have only two coordinates, β and θ. How are they related?
 
I guess you are right but that is the exact question that I m looking for the answer, how are they related:)
 
Really? It's basic geometry. Consider the height of point B.
 

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