A disc of mass 4 kg and radius 6 metre is free to rotate in horizontal plane about a vertical fixed axis passing through its centre. There is a smooth groove along the diameter of the disc and two small blocks of masses 2 kg each are placed in it on either side of the centre of the disc as shown in figure. The disc is given initial angular velocity `omega_(0)` =12 rad/sec and released. Find the angular speed of disc (in radian/sec) when the blocks reach the ends of the disc.

Answer

4