4.0 kg block A and 6.0kg block B are connected by a string of negligible mass. Force a Fa = 12N acts on block A; force B Fb = 24N acts on block B. What is the tension in the string. I was able to draw FBD and lists all the forces acting on A and B, but what I don't understand is the tension T acting on A and B. A: Fa - Ta = m1 A B: Fb - Tb = m2 A In my understanding, Ta and Tb shouldn't be equal, since we have Fa and Fb exerts on each object and they have different value. What if Ta > Tb, then the cord between A and B should come loose, therefore we'd not have tension at all. But if we don't have have Ta = Tb, then there's no way we can solve the problem...... So my question is: Is it really Ta = Tb and why ?