Blocks on a slant(with friction)

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The discussion centers on analyzing a system of three blocks on a frictionless incline, with a force applied to the first block. Participants are asked to draw free body diagrams for each block, determine the system's acceleration, net forces on each block, and the contact forces between them. One user attempts to calculate acceleration using an equation that incorrectly incorporates friction and omits the applied force. The importance of applying Newton's second law to each block individually or to the entire system is emphasized for accurate analysis. Clarification on the correct approach and equations is sought to resolve the problem effectively.
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This is the problem:

Three blocks on a frictionless incline are in contact with each other as shown in the following figure. A force F is applied to block 1 (mass m1), so the whole system moves up the incline.
a) Draw a free body diagram for each block.
b) Determine the acceleration of the system.
c) Determine the net force on each block.
d) What is the force of contact that each block exerts on its neighbor?

I can draw the free body diagram

I tried to determine the acceleration by saying

a=[(g*sin(angle))-(mu*g*cos(angle))]/[(m1+m2+m3)]

I think Fnet= Fp-Ffr

I also think the Fcontact=Fp*number of sides in contact with another block


Please any help would be much appreciated3
 
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rphmy said:
I can draw the free body diagram
Use that to apply Newton's 2nd law to each block.

I tried to determine the acceleration by saying

a=[(g*sin(angle))-(mu*g*cos(angle))]/[(m1+m2+m3)]
Where does this come from? Note that this equation has friction and leaves out the force F. It doesn't even have the right dimensions.

Apply Newton's 2nd law to each block separately. You can also apply it to all three blocks considered as a single system.
 
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