Mechanics of Machines and Vibrations PROBLEMS Balancing of Rotating Mass Problem 1 Figure P1 shows a shaft with 3 m span between two bearings A and B carries two discs X and Y rotating at a constant speed 500 rpm. Initially the discs are totally balanced. Modifications are made on the discs as follows:- (1) (2) On disc X, add mass of 1 kg at radius 3 cm at 90 and remove mass of 1 kg at radius of rotation of 4 cm at 0. On disc Y, add mass of 1 kg at radius 3 cm at 270 and remove mass of 1 kg at radius of rotation of 4 cm at 180. For these conditions determine the following:- The dynamic forces on bearings A and B. The total forces on bearings A and B if mass of disc X and Y are 10 kg each. The total maximum forces on bearings A and B. i. ii. iii. iv. The maximum and minimum vertical forces on bearings A and B. (Note: Use given reference of direction to solve the problem). [45.7 N; 45.7 N; 130.8 N; 79.5 N; 143.8 N; 143.8 N; 70.6 N; 125.6 N] Disc X 1 m. 1 m Disc Y Reference 90 180 B 0 + 0 270 X Y Removed mass Added mass Figure P1