How to find the acceleration of a block being pushed

AI Thread Summary
To find the acceleration of the blocks, start by analyzing the forces acting on each block using free-body diagrams. The applied force on the lower block must overcome static friction to initiate motion, which has been calculated as 111.034 N. The acceleration for the upper block (m1) was initially calculated as 0.98 m/s², but some participants believe this value is too low. The acceleration for the lower block (m2) can be derived from the net force acting on it, factoring in the kinetic friction with the table. Understanding the relationship between the forces and the masses will clarify the acceleration for both blocks.
friar
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A block of mass m1 = 4.60 kg sits on top of a second block of mass m2 = 15.3 kg, which in turn is on a horizontal table. The coefficients of friction between the two blocks are µs = 0.300 and µk = 0.100. The coefficients of friction between the lower block and the rough table are µs = 0.500 and µk = 0.400. You apply a constant horizontal force to the lower block, just large enough to make this block start sliding out from between the upper block and the table.
(a) Draw a free-body diagram of each block, naming the forces on each. (Do this on paper. Your instructor may ask you to turn in this work.)

(b) Determine the magnitude of each force on each block at the instant when you have started pushing but motion has not yet started. In particular, what force must you apply?
(c) Determine the acceleration you measure for each block.

a is easy. I figured out b to be 111.034N. The first acceleration (m1) i figured out to be .98 m/s^2. I have no idea how to find the acceleration for m2. If you could please give me an idea of what to do I'd really appreciate it.
 
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Welcome to PF, Friar!
Agree with your 111 N. I don't see how you got the 0.98. I got a much larger answer.

Isn't the acceleration for m2 obviously given in the question?
 
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