Tension in rope between blocks on an incline

[Alvin92SD]

1. Two blocks made of different materials connected together by a thin rope, slide down a plane ramp inclined at an angle θ to the horizontal (block B is above block A). The masses of the blocks are mA and mB, and the coefficients of friction are μA and μB. If μA < μB, find the tension in terms of mA, mB, and θ



2. The first part of the question is to find the accelearation, a, which I've done and got the correct answer. Finding the tension is the second part of the question, which I've no idea at all how to do. Also, I'm not sure I really understand what tension is.



3. I've tried T=Fa-Fb ,but I didn't get the answer.

 

[Spinnor]

Did you draw a free body diagram? There are three forces acting on each block, two of which you know (if you got the acceleration right). You know that the sum of the forces in the direction of motion is equal to m*a. You have a component of the weight force in the direction of motion, you have the friction force, and you have the unknown tension. The mass should cancel out.

 

[Alvin92SD]

Thank you, I've got the right answer now.