## brinethery 3 years ago A block with mass m1 = 8.6 kg is on an incline with an angle θ = 35.0° with respect to the horizontal. The coefficients of friction are: μk = 0.32 and μs = 0.352. Now a new block with mass m2 = 16.9 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?

1. brinethery

2. brinethery

Something is just wrong with my free-body diagram. I keep getting the wrong answer. I'm suck somewhere, I just don't know which step at this point. :-(

3. brinethery

*stuck... lol

4. gerryliyana

|dw:1351678973651:dw|

5. gerryliyana

where N1 = m1 g cos theta, and N2 = m2 g cos theta

6. gerryliyana

@brinethery

7. brinethery

Thank you very much. I just woke up and am trying to resurrect with coffee. I will go over the problem later on and see if I come up with the right answer :-). I appreciate your help.