1. The problem statement, all variables and given/known data In an Atwood's Machine, the larger mass is 1.8kg and the smaller mass is 1.2. (A)Ignoring friction what is the acceleration of the masses? (B)What is the tension of the string. - I know you have to find the acceleration to get the tension but i dont know how to find the acceleration. I think you replace net force with T-(the mass) ut i am also unsure of why you do that.