1. The problem statement, all variables and given/known data A unifrom disc A of radius 2m is cut as shown in the image. The cut out is also a disc of radius 1m. Find the distance of the two center of gravity before and after the paper disc is cut. http://crossfacer.com/circle.jpg [Broken] 2. Relevant equations x=m1x1/M+m2x2/M+...... 3. The attempt at a solution Mass of the disc is proportional to its area. so mass of disc A=2^2pi=4pi units mass of disc being cut out=1^2pi=pi units Let x be the distance between the two centers of gravity. (4pi-pi)(2-x)=(4pi)(2)-(2+1)(pi) x=0.333m This question is quite difficult for me. I don't have much confidence on my answer.:tongue2: May anyone try it?