Moving Constraints: Virtual Work in Classical Mechanics

[Sumit Dey]

the virtual work done in the case of moving constraints is obviously not zero(argument as shown in classical mechanics by r douglas gregory page 345 under the heading of Lagrange's equations with moving constraints.i just wanted to understand how come the virtual work done the constraint forces in still zero even in the time dependent cases. why is he just taking into consideration of the partial derivative of the position vector r_i wrt to the generalized coord q_ j only and not the time derivative while taking the dot product with the virtual velocity.. please help!

 

[Greg Bernhardt]

Thanks for the post! Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?