Four particles of masses m, m, 2m and 2m are placed at the four corners of a square of side a as shown in the figure. The (x, y) coordinates of the centre of mass are
(a2,2a3)
The (x, y) co-ordinates of the centre of mass are given by
x=m1x1+m2x2+m3x3+m4x4m1+m2+m3+m4=m×0+m×a+2m×a+2m×0m+m+2m+2m=a2
and y=m1y1+m2y2+m3y3+m4y4m1+m2+m3+m4=m×0+m×0+2m×a+2m×am+m+2m+2m=2a3
Hence, the correct choice is (c).