What is the Angular Momentum of a Bent Plate Rotating at 30rad/sec?

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Homework Statement


The bent plate has a mass of 70kg per square meter of surface area and revolves about the z-axis at the rate w=30rad/sec. Determine the angular momentum H of the plate about the z-axis. (Neglect the mass of the hub and the thickness of the plate)

http://img839.imageshack.us/img839/9853/angularmomentum.jpg

Homework Equations


w=w k
HG=-Izzwzi-Izywzj+Izwzk


The Attempt at a Solution


Splitting the bodies into various parts and calculating. However, as it is about the axis, and not the point, confused.
 
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You would use the parallel axis theorem to move the moments of inertia from centroidal points to the axis of rotation. Then determine the angular momentum.
 
Show us what you actually did. It's hard to figure out what's confusing you if all you give us is a vague description of what you tried.
 
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