1. The problem statement, all variables and given/known data he coefficient of static friction is 0.682 between the two blocks shown. The coefficient of kinetic friction between the lower block and the floor is 0.119. Force F causes both blocks to cross a distance of 6.95 m, starting from rest. What is the least amount of time in which the motion can be completed without the top block sliding on the lower block, if the mass of the lower block is 1.64 kg and the mass of the upper block is 2.41 kg? 2. Relevant equations Fk=[itex]\mu[/itex]N Fs(max)=[itex]\mu[/itex]N 3. The attempt at a solution First I found the max static friction which was 16.107N. Then I found the kinetic friction which was 4.723N. First I tried to just subtract the static from kinetic, and then use that as the pushing force, which resulted in a=2.81m/s/s but when I used that acceleration in kinematics equation I did not get the correct answer (i got 2.22s, I don't know what the correct answer is) I also then saw this thread and tried the method.https://www.physicsforums.com/showthread.php?t=533845" I split it into the two masses on a string as described, but I got confused at what to do when concentrating on m1. Would this method be what I need to use, or is there another way I can solve this problem.