1. The problem statement, all variables and given/known data 2. Relevant equations a=Rα 3. The attempt at a solution Free body diagrams: For larger pulley, TR=Iα ⇒ T=½MRα If this pulley rotates by some amount suchat x length of rope becomes free, and if I hold the smaller pulley at rest, then this extra length of rope comes bellow the pulley. So the small pulley can go down by x/2 distance. Hence for every θ rotation, the small pulley goes down by Rθ/2. For smaller pulley, T'-2T+Mg/2=Ma/2 and for block, T'=Ma+Mg So ssubstituting T', 2T-Ma/2=3Mg/2 Now if rope comes down at a rate of Rα, then pulley goes down by Rα/2 Hence a=Rα/2 After plugging in all values, I am not getting the answer.