Find coordinates of mass center of a quarter ring of radius r placed in the first quadrant of a Cartesian coordinate system, with centre at origin.

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.

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.

Find coordinates of mass center of a semicircular ring of radius r placed symmeric to the y-axis of a Cartesian coordinate system.

Find coordinates of mass center of a uniform semicircular plate of radius r placed symmetric to the y-axis of a Cartesian coordinate system, with centre at origin.

Find coordinates of mass center of a uniform semicircular plate of radius r placed symmetric to the y-axis of a Cartesian coordinate system, with centre at origin.

Find coordinates of mass center of a uniform semicircular plate of radius r placed symmetric to the y-axis of a Cartesian coordinate system, with centre at origin.

What is meant by Cartesian coordinate system?