A disc of radius R is cut from a disc of radius 2R such that the edge of smaller disc touches the edge of original disc. What will be the centre of mass of left plate.
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3 Answers
62Let the center of the large disk be the origin.
Now, we know that the smaller disk is cut out. So, in one way, we can consider it having a mass of -m!
The larger disk will have mass 4m
So the smaller disk is at a distance of r from the center of the large disk.
So the CM={(0).(4m)+R.(-m)}/(4m-m) = -R/3
So, the center of mass is at the distance R/3 from the center of the large mass, but away from the hole that is caused by the taking away of the disk.
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