A rotating door is made from four rectangular glass panes, as shown in the drawing. The mass of each pane is 76 kg. A person pushes on the outer edge of one pane with a force of F = 55 N that is directed perpendicular to the pane.(adsbygoogle = window.adsbygoogle || []).push({});

a.) Find the rotational inertia of the door.

b.) Find the magnitude of the door's angular acceleration.

c.) Find the time it would take to rotate the door a half-circle (assuming it started from rest.)

I have tried calculating the torque for the pane to be (1.2m)(55N) = 66 Nm. I think the rotational inertia should be I = 1/3ML^2 multiplied by 4 for each pane since it is spinning away from the center of mass (edge). Can someone tell me if this is correct? I don't know how to continue this problem...Thanks.

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# Homework Help: Rotational Inertia of a door

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