How Is the Mass of Block B Calculated in a Friction-Affected Pulley System?

AI Thread Summary
In a friction-affected pulley system, block A, with mass mA, slides down an incline at a constant speed, indicating zero acceleration. The forces acting on block A include gravitational components and friction, described by the equation F = ma. The tension in the rope is equal on both sides, leading to the calculation of block B's mass as [mA * g * sin(theta) - mA * g * cos(theta) * Uk] / g. This formula effectively expresses the mass of block B in terms of the known variables. The solution has been verified as correct.
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Homework Statement



In figure 6-36, two blocks are connected over a pulley. The mass of block A is mA and the coeffcient of kinetic friction between A and the incline is Uk. Angle of the incline is theta. Block A slides down the incline at constant speed. What is the mass of block B? Express your answer in terms of the variables given.

http://img121.imageshack.us/img121/9748/fig636.gif

Homework Equations



F = ma

The Attempt at a Solution



Taking acceleration to be 0, because speed is constant. And that T1 = T2, i came to the answer of

[m1gsin(theta) - m1gcos(theta)Uk] / g = mass of the 2nd block

Can I get a verification
 
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Yes, that is correct.
 
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