When three blocks are released from rest, they accelerate with a magnitude of 0.500 m/s2. Block 1 has mass M, block 2 has 2M, and block 3 has 2M. What is the coefficient of kinetic friction between block 2 and the table?
(The blocks are arranged with block 1 hanging from the left side of the table, block 2 sitting on the middle of the table, and block 3 hanging from the right side of the table. All connected by an ideal rope.)
The Attempt at a Solution
This is the problem. I have no clue where to start. The only thing I know is that the coefficient of friction is uk and has no units. I understand that I must use the first formula somehow. Would I first find the normal force of block 2? I'm lost...