angular velocity and angular acceleration not nothing

[Albertagort]

in this exercise, the first you find in the link http://dimeca.unica.it/didattica/materie/ruggiu/prove/esercizi_cinematica.pdfthe angle velocity w2 turns out nothing. I deduce that then move motion translatory. I'm supposed to assume that even angular acceleration is nothing. However, after a procedure which is not clear to me to tell the truth, it finds an acceleration not nothing. the same reasoning applies to body 3, in which the angle velocity, from the first result, seems to be constant.

thanks to those who will help me solve this doubt

 

[Fulvio Romano]

in this exercise, the first you find in the link http://dimeca.unica.it/didattica/materie/ruggiu/prove/esercizi_cinematica.pdfthe angle velocity w2 turns out nothing. I deduce that then move motion translatory. I'm supposed to assume that even angular acceleration is nothing. However, after a procedure which is not clear to me to tell the truth, it finds an acceleration not nothing. the same reasoning applies to body 3, in which the angle velocity, from the first result, seems to be constant.

thanks to those who will help me solve this doubt

I press that I did not follow the calculations in detail. Sorry.
the fact that the angle speed is nothing means, as you correctly say that the act of motion is a pure translation (at the limit nothing). Why should angular acceleration be nothing?
Think of a pendulum. when it is in one of the highest points how much angular speed is worth? Of course zero, but acceleration? is the maximum possible (with that energy configuration).

Moreover if the rod does not rotate, and the angular acceleration is zero, the rod has no hope of ever starting to rotate again, does it?

 

[Albertagort]

Thank you, I've been helpful. In fact, I'm back.