Marie and Maria each send a spinning uniform disc towards th…
Marie and Maria each send a spinning uniform disc towards the center of an axle. Marie’s disk has a mass of 0.5 kg with a radius of 15 cm and spins about the axle at a rate of 120 rpm. Maria’s disk also has a mass of 0.5 kg, but a radius of 20 cm, and it spins in the same direction as Marie’s at a rate of 150 rpm. The two discs then collide and stick together. What is their final rotational speed in rad/s?