Not slip sliding away
Two blocks are on top of each other on an inclined plane angled 30 degrees with respect to the horizontal. The top block has a mass of 30 kg, while the bottom block has a mass of 50 kg. I connect a rope to the higher end of the top block, run it through a pulley, and connect the other end of the rope to the higher end of the bottom block. If the coefficient of static friction is the same between all surfaces, what is its minimum value if the blocks are not to slip?