Moment of inertia of door rotation

AI Thread Summary
The moment of inertia for the 23 kg solid door, calculated for rotation about a vertical axis 17 cm from one edge, is determined using the formula I = I_cm + MR^2. The calculation yields a moment of inertia of 3.87 kg*m^2, where I_cm is derived from the door's dimensions and mass. The distance R is correctly identified as the distance from the center of mass to the axis of rotation. Verification through integration confirms the accuracy of this result. The calculations and method employed are deemed correct by participants in the discussion.
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Homework Statement


A 23 kg solid door is 220 cm tall, 95 cm wide. What is the door's moment of inertia for rotation about a vertical axis inside the door, 17 cm from one edge?

Homework Equations


I = I_cm + MR^2

The Attempt at a Solution


I = I_cm + MR^2

I = (1/12)(23kg)(0.95m)^2 + (23kg)((.95m/2) -.17m)^2

I = 1.73 +2.14 = 3.87kg*m^2
If this is wrong then I am not sure I am using right value for R. I am using the distance from the center of mass for the door which i think is middle of door. So .17m from edge would be .95/2 - .17 = .305 = R

thanks for any help
 
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That looks completely correct to me.

I checked it with integration of mr^2 across the width of the door and got the same answer.
 
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