Moments of Inertia: Finding Center Point of Semicircle

teng125
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can anyone tell me how to find moments of inertia for the centre point of a semicircle??
 
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Do you know the definition of a moment of inertia?
 
Let the mass of the semicircle be M and the radius be R.
Express the mass of a differentiable element dm in terms of d(theta).
Then in the actual process of finding centre of mass replace dm by d(theta) of integrting the X-cordinates and Y co-rdinates of the point on the semicircle in terms of theta and dividing the whole with M. I think you know this calculus based procedure to find cenre of mass for continuous objects as asked by TD
 
teng125 said:
can anyone tell me how to find moments of inertia for the centre point of a semicircle??
There is a very simple method, if you know the MoI of a circle, but to expect help in this forum you must show some effort on your part. Please read the rules for this forum (see my signature).
 
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