A uniform, solid cylinder with mass M and radius 2R rests on a horizontal table. A string is attached by a yoke to a frictionless axle through the center of the cylinder such that the cylinder can rotate about the axle at the center. The string runs over a disk-shaped pulley with mass M and radius R that is mounted on a frictionless axle through its center. A block of mass M is suspended from the free end of the string. The string doesn't slip over the pulley and the cylinder rolls without slipping on the table. Find the magnitude of the acceleration of the block after the system is released from rest.

http://d2vlcm61l7u1fs.cloudfront.net/media%2Fdc4%2Fdc4f96b6-0be4-4f29-989e-e8f55bae7a4a%2Fphp37KBHS.png