The Great Pyramid of Cheops at El Gizeh, Egypt, had a height H = 148.6 m before its topmost stone fell. Its base is a square with edge length L = 227.4 m. Its volume V is equal (L^2)H/3. Assuming that it has uniform density p(rho) = 1.8e3 kg/m^3.(adsbygoogle = window.adsbygoogle || []).push({});

(a) What is the original height of its center of mass above the base?

(b) What is the work required to lift all the blocks into place from the base level?

Kay, so I'm good with finding center of mass in one dimension, but in two and three dimensions, it is confusing the hell out of me. Am I supposed to integrate? If so, what? I just need a push in the right direction (I think).

Also, for finding the work, I'm guessing I'm supposed to use the CM height as the distance for all of the blocks traveled, but I'm not sure about that either. Any help would be appreciated!

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# Homework Help: Great Pyramid of Cheops (Center of Mass Problem)

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