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Homework Statement
The coefficient of friction between A and the table is μ_{A}.
The coefficient of friction between A and B is μ_{B}.
A, B, C and D all move with an acceleration of 2m/s^2 (A and B move to the left).
Find the force that the friction between the bodies apply on B.
Find the tension of the yarn that connects A and C.
Find the mass of D.
At a certain moment, the yarn which connects A and D is torn. Will A and B still move together? (Show with calculations)
m_{A}=1.4kg ,m_{B}=0.6kg, m_{C}=2kg, μ_{A}=0.2, μ_{B}=0.75, a=2m/s^2
*Both times the static and dynamic coefficients are equal.
Homework Equations
F=ma
The Attempt at a Solution
The last question is what I am stuck in, but I don't have the answers so I will show my calculations prior to that.
Forces on A and B: (I hope everything is clear)
m_{B}g=6N so N_{B}=6N, now we could see that according to ma=F, 1.2=F, so the force is 1.2N.
Now if we look at C we could see that 4=T_{C}20, T_{C}=24N.
Now if we look at A we could see that: m_{A}g=14N, so N_{A}=20N.
Using ma=F: 2.8=T_{D}1.2240.2*20 so 2.8=T_{D}29.2, T_{D}=32N
Looking at D: 2m_{D}=10m_{D}T_{D}, m_{D}=4kg.
Now I am not sure what to do, I tried to draw the forces again, but from there I don't really know what to do. How can I know if C moves now? If it doesn't then A and B doesn't move, but if it does I don't know how to reach the answer.
Thanks in advance!
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