The troublesome topic of Galilean invariance in Lagrangian mechanics is discussed in two situations: (i) A particular case involving a rheonomic constraint in uniform motion and (ii) the general translation of an entire system and the constants of motion involved. A widespread impropriety in most textbooks is corrected, concerning a condition for the equality h = E to hold.
References
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; in this book the authors argue that L is a Galilean invariant but in fact they show that it is the Lagrange equations that are so.4.
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2015
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