An unbalanced machine can be approximated by two masses, 2 kg and 1.5 kg, placed at the ends A and B respectively of light rods OA and OB of lengths 0.7 m and 1.1 m. The point O lies on the axis of rotation and OAB forms a plane perpendicular to this axis; OA and OB are at right angles. The machine rotates about the axis with an angular velocity ω, which gives a centrifugal force mrω² for a mass m and rod length r. Find the unbalanced force at the axis. To balance the machine a mass of 1 kg is placed at the end of a light rod OC so that C is coplanar with OAB. Determine the position of C.