Free vibration of two rotor system The flywheel of an engine driving a dynamo has mass of 200kg and has a radius of gyration of 30cm. The shaft at the flywheel end has as an effective length of 25cm and is 5cm diameter. The armature mass is 225kg and has a radius of gyration of 25.5cm.The dynamo shaft has a diameter of 4.375cm and an equivalent length of 20cm.Calculate the frequency of the torsional vibration and the position of the node. The modulus of rigidity for the shaft material is 80GN/m Flywheel Dynamo B 15 cm 14.375 cm 25 cm 20 cm