1. The problem statement, all variables and given/known data In figure shown, pulleys are ideal m1 > 2 m2. Initially the system is in equilibrium and string connecting m2 to rigid support below is cut. Find the initial acceleration of m2? 2. Relevant equations 3. The attempt at a solution In equilibrium, 2T1 = T2 For block m1 , T2 = m1g For block m2, T1 = m2g + T3 When the string is cut,let the initial acceleration be 'a' 2T1 = T2 For block m1 , m1g - T2 = m1a/2 For block m2 ,T1 - m2g = m2a This gives , a=2(m1-2m2)g/(m1+4m2) ,which is incorrect answer . I would be grateful if somebody could help me with the problem .