1. A man, denoted as A and having a mass m, is connected to a block, denoted as B, with a mass of m/2. They are linked by a string passing over a pulley, as illustrated in the figure on the right. The pulley itself has a radius R, and its mass m/4 is uniformly distributed along its circumference. It's important to note that the string does not slip on the pulley. The entire system is released from rest, and as a result, man A starts climbing the string with a constant speed relative to the string. Determine the acceleration of the block B. B