Generalized coordinates in Lagrangian mechanics

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SUMMARY

In Lagrangian mechanics, generalized coordinates can encompass a variety of dimensions beyond traditional length and angles, including energy, length squared, or even dimensionless quantities. The fundamental form of Lagrange's equations remains unchanged regardless of the units of the coordinates employed. An example includes transforming a length by dividing it by the speed of light, resulting in a new coordinate expressed in time units. This flexibility in coordinate choice allows for diverse applications in mechanics.

PREREQUISITES
  • Understanding of Lagrangian mechanics
  • Familiarity with generalized coordinates
  • Basic knowledge of dimensional analysis
  • Concept of coordinate transformation
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ShayanJ
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In some texts about Lagrangian mechanics,its written that the generalized coordinates need not be length and angles(as is usual in coordinate systems)but they also can be quantities with other dimensions,say,energy,[itex]length^2[/itex] or even dimensionless.
I want to know how will be the Lagrange's equations in such coordinates?
Could you give an example whose proper coordinates are as such?
Thanks
 
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Lagranges equations are unchanged regardless of the units of the coordinates. You can take any problem with lengths and angles and simply do an arbitrary change of variables to get a coordinate in any units you like. E.g. Take any length and divide by the speed of light and you have a new coordinate with units of time.
 
tbf, angles are dimensionless so there's no issue there.
 

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