Block A of mass 2m hangs from a cord that passes over a pulley and is connected to block B of mass 3m. Block B is free to move on a frictionless horizontal surface. The pulley is a disk with frictionless bearings, having radius R and moment of inertia 3MR^2. Block C of mass 4m is on top of block B. The surface between blocks B and C is not frictionless. shortly after the system is released from rest, block A moves with a downward acceleration a, and the two blocks on the table move relative to each other.(adsbygoogle = window.adsbygoogle || []).push({});

a.) In terms of the given quantities and g, find the tensions, T1 and T2 for each section of string.

For this I have the Sum of Fy= 2m(g-a)=T1 for Fx= T2= 7ma which the anwer given is different. The t1 is correct! But is this a typo or am I wrong?

b.) If a=2m/s^2, determine the kinetic coefficient of friction between blocks B and C.

I was thinking the force of friction would be equal to the tension in the x direction but when I work that out I dont get the right answer. Is that the right concept?

c.) What is the acceleration of block C at this time?

I dont have any work for this part yet but I'll put it on here just in case.

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# Homework Help: Determine the kinetic coefficient of friction

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