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Mamtaatal
A disc of radius R is cut out from a larger disc of radius 2R in such a way that the edge of. The hole touches the edge of the disc. Locate the centre of mass of residual disc.
Try finding the center of mass of what the entire mass would be and what the center of mass of the cutout would be. The center of mass of the entire disk (the origin) will be the weighted average of the cutout and the residual disks' centers of mass.
x=(m1x1+m2x2)/(m1+m2). And you find x=R/3, situated to the left of the previous center of mass.
Yes, the answer would be R/3. Easy question