as in the diagram below, mass m1 is placed above mass m2 on a sloped incline with an angle of b degrees. the frictional coefficient between the two masses is C1 and the coeficient between mass 2 and the slope is C2.

find the acceleration of the masses.

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after dividing the vectors into components i said

N1=(m1)gcosb

f1=(C1)(m1)gcosb

N2=N1+(M2)gcosb=(M1+M2)gcosb

f2=(C2)(M1+M2)gcosb

for mass 1

F=m1gsinb-f1=m1a

=(m1)gsinb-(C1)(m1)gcosb=m1a

a1=g(sinb-C1cosb)=gcosb(tgb-C1)

meanin that when C1 is equal to tanb, body 1 will not move relative to body 2 or will not move relative to the slope?

now for body2

F=m2gsinb+f1-f2=m2a------> is this correct??

after opening i get

a2=m2gcosb(tgb-C2)+m1gcosb(C1-C2) is this correct?