I do not know the formula I am suppose to use for this help please!

A solid disk of mass M = 0.650 kg and radius R 2 [L450 n1 is suspended vertically and is free to rotate about its center without friction. A point object that has the same mass as the disk is placed at an angle 9. = 2511' clockwise from the top along the rim. causing the disk to rotate. The acceleration due no gravityr is g = 9.30 mfsz. What is the angular speed air of the disk when the object is directly.r below the center of the disk. MEWS