Rotation Problem, I'm confused on this one

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.0100kg particles have been glued to a rod of Length L=6.00cm and negligible mass and can rotate around a perpendicular axis through point O at one end. How much work is required to change the rotational rate (a) from 0-20.0 rad/s, (b) from 20.0 rad/s to 40.0 rad/s, and (c) from 40.0 rad/s to 60 rad/s? (d) what is the slope of a plot of the assembly's kinetic energy in joules versus the square of its rotational rate (in radians-squared per second squared)?

----->The question in my mind is the rotation. Is the mass rotating about O? Or is it rotating around the rod? You have to figure the moment of inertia. The radius of the rod is not given, if the rod is rotating on its axis. And, the total mass is not given "0.0100kg particles" is all that is mentioned. I've been working on this problem for hours and don't understand how to finish it and it
s due tomorrow and I have so much left to do in my other classes:cry:
 

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Cannot yet see your diagram so I do not know where the masses are or how many. The problem says it is rotating about a perpendicular axis- that means perpendicular to the length of the rod.
 
The diagram is on now, it just takes alittle while to load.
 
PremedBeauty said:
The diagram is on now, it just takes alittle while to load.

Unfortunately it is not on.
 
Set up the work-energy theorem!
 
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