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Three stage lights are mounted on a pipe fixture as shown. The lights at A and B each weigh 4.1 lb, while the one at C weighs 3.5 lb. The fixture weighs 6 lb and has a centroidal radius of gyration of 24 in. The centroid of the pipe can be assumed to be 42 in. from point D. If the connection at E fails so that the lights and fixture rotate about point D, determine the angular acceleration of the system immediately after the failure at E. Assume point D can be treated as a pinned connection and the lights can be modeled as particles.
Fig. P16.85
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