Two blocks with mass m1 = 4.2 kg and m2 = 4.7 kg are connected by a massless string over a frictionless and massless pulley. The angle of the incline is equal to 27.5°. The kinetic coefficient of friction between m1 and the incline is 0.28. What is the minimum value of the static friction coefficient that will prevent m1 from starting to move if it is at rest.


Find the magnitude of the acceleration of the system if m1 is moving up the incline.

Find the magnitude of the acceleration of the system if m1 is moving down the incline.

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