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Exidez
Oct7-03, 09:44 PM
i have a question which i have been told about but i still dont udnerstand...
ok..
you have two objects(say they are made out of wood):

1: *-------------* ...... 2: *---------
..............|................................... .|
..............|................................... .|
..............|................................... .|
..............|................................... .|
..............|................................... .|
..............|................................... .|

"*" represents 1kg wieghts
"..." represent nothin, i needed to put those there so the picture would position correctly. Just say it is open air :)

you supply a torque to object number 1, you will notice that is spins perfectly. While if you supply a torge to number 2 it will wobble and isnt perfect like number 1.

so what i want to know is.. why does number 2 wobble?

its hard to explain the question, but i hope you all understand

also the torque is supplied at the rod:
........|
........|
........|
........|
........|

Jonathan
Oct8-03, 01:47 AM
Number two wobbles because there is an unbalanced centripetal acceleration. Given a point mass at radius r, and instantaneous velocity v, centripetal acceleration c is given by:
c=(v^2)/r
or if you use angular velocity (w is omega):
c=(w^2)r
In case you usually use rpm, I think v=rpm*Πr/30 and w=rpm*Π/30.