A block with mass m1 = 9.0 kg is on an incline with an angle θ = 30.0° with respect to the horizontal. For the first question there is no friction, but for the rest of this problem the coefficients of friction are: μk = 0.27 and μs = 0.297.
Now a new block with mass m2 = 16.4 kg is attached to the first block. The new block is made of a different material and has a greater coefficient of static friction. What minimum value for the coefficient of static friction is needed between the new block and the plane to keep the system from accelerating?

Question

A block with mass m1 = 9.0 kg is on an incline with an angle θ = 30.0° with respect to the horizontal. For the first question there is no friction, but for the rest of this problem the coefficients of friction are: μk = 0.27 and μs = 0.297.
Now a new block with mass m2 = 16.4 kg is attached to the first block. The new block is made of a different material and has a greater coefficient of static friction. What minimum value for the coefficient of static friction is needed between the new block and the plane to keep the system from accelerating?