- #1

Ahmed1029

- 109

- 40

I know that when a system consists of N particles and p constraints, it has 3N-p degrees of freedom; this is the definition. Then I come across something like this example in the picture above, in which I have a wire which includes an infinite number of particles, and in the solution it's completely ignored. Here there are 2 constraints and the auther treated the whole setup as if there is only one particle while the wire is completely ignored, thus the system has one degree if freedom because 3(1)-2=1

In general, how do I know the number of degrees of freedom of a "mechanical system" that is not just made of ordinary accumilatios of discrete particles?