Pulley system on a double inclined plane

From Mech

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This article is about the following scenario. A fixed triangular wedge has two inclines I1 and I2 making angles α1 and α2 with the horizontal. A pulley is affixed to the top vertex of the triangle. A string through the pulley has attached at its two ends blocks of masses m1 and m2, resting on the two inclines I1 and I2 respectively. The string is inextensible. The coefficients of static and kinetic friction between m1 and I1 are μs1 and μk1 respectively. The coefficients of static and kinetic friction between m2 and I2 are μs2 and μk2 respectively. Assume that μk1μs1 and μk2μs2.

Summary of cases starting from rest

Case What happens qualitatively Magnitude of accelerations
m1sinα1m2sinα2>μs1m1cosα1+μs2m2cosα2 m1 slides downward and m2 slides upward, with the same magnitude of acceleration a=g(m1sinα1m2sinα2μk1m1sinα1μk2m2sinα2)/(m1+m2).
m2sinα2m1sinα1>μs1m1cosα1+μs2m2cosα2 m2 slides downward and m1 slides upward, with the same magnitude of acceleration a=g(m2sinα2m1sinα1μk1m1sinα1μk2m2sinα2)/(m1+m2).
|m1sinα1m2sinα2||μs1m1cosα1+μs2m2cosα2| The system remains at rest 0