Learn How to Use Lagrangians for Statics: Building Compound Shapes and Examples

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Using Lagrangians for statics is possible by equating the Lagrangian to potential energy, which can be particularly useful in analyzing equilibrium conditions. In cases like building a compound shape such as a bridge from constrained point masses, the potential energy approach often yields more straightforward results. The discussion highlights the catenary as a relevant example, emphasizing the importance of minimizing potential energy in equilibrium scenarios. The Lagrangian mechanics approach involves a more complex minimization process compared to traditional potential energy methods. Overall, understanding these principles can enhance the analysis of static structures.
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Is it possible to do statics using lagrangians? (specifically building up a compound shape like a bridge from constrained point masses). Where could I see an example of this?
 
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least_action said:
Is it possible to do statics using lagrangians? (specifically building up a compound shape like a bridge from constrained point masses). Where could I see an example of this?

Yes, just put the Lagrangian equal to the potential energy. However I think you will find that, if you have an equilibrium the potential energy is at minimum more useful. For example consider the cantenary.

V=\int_C my\,ds

Now if you use Lagrangian mechanics you would be minimising \iint_C my\,ds\,dt instead of \int_C my\,ds
 
fobos3 said:
Yes, just put the Lagrangian equal to the potential energy. However I think you will find that, if you have an equilibrium the potential energy is at minimum more useful. For example consider the cantenary.

V=\int_C my\,ds

Now if you use Lagrangian mechanics you would be minimising \iint_C my\,ds\,dt instead of \int_C my\,ds

Thank you!
 
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