1. The problem statement, all variables and given/known data http://imgur.com/vgLv6NY The figure shows a system of masses and pulleys. Assume the masses slide without friction and the pulleys have negligible mass. Calculate the tension in the string. Data: M1 = 2.1 kg; M2 = 1.4 kg; M3 = 1.6 kg; 2. Relevant equations f=ma 3. The attempt at a solution I don't know what it is about this pulley system that is throwing a wrench in the cogs but I just can't find the correct answer. I know that the acceleration of M1 will be lower than that of M2. I also believe that the acceleration of M3 must equal that of M1 + M2. a1=(M3g-M2a2) / (M1+M2+M3) Similar for a2. a3=M3g / (M1+M2+M3) Are my assumptions correct? I tried to use these equations to solve for a2. Since a2 is the limiting factor on the tension due to it being the lightest of the two resisting forces the total tension should just be equal to M2*a2. What I got: a2=0.76541 m/s Tension=m2*a2=1.072 N Does that sound right? Thank you!