Find coordinates of mass center of a quarter sector of a uniform disk of radius r placed in the first quadrant ofa Cartesian coordinate system with centre at origin.

Explanation

Making use of the result obtained in the previous example, distance OC of the mass center form the center is `OC=(2rsin(pi/4))/((3pi)/4)=(4sqrt(2)r)/(3pi)` Coordinates of the mass center `(x_c, y_c)` are `((4r)/(3pi), (4r)/(3pi))`