What Is the Acceleration of Block C if the Rope Between A and B Is Cut?

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When the rope between blocks A and B is cut, the tension in that segment becomes zero, which affects the forces acting on block C. The initial calculations incorrectly assumed that the tension of 7.31N would still apply after the cut. The relevant force for determining the acceleration of block C should consider the weight of block C and the kinetic friction acting on it. The coefficient of kinetic friction is 0.36, and the weight of block C is 25.3N. Clarification on the value of gravitational acceleration (g) is necessary, as the problem does not specify it, but using 9.80 m/s² may not be appropriate in this context.
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Homework Statement



3 blocks A B C are connected by strings as in attached image. The block C is descending with constant velocity. I've worked out the tension in string A B to be 7.31N. The coefficient of kinetic friction between each block and the surface is 0.36 and block a b weighs 20.3N each. I've also calculated the weight of C to be 25.3N. The last part of the question asked for the acceleration of block C if the rope between A B is cut.

Homework Equations



Link to figure

http://b.imagehost.org/view/0603/YF-05-56.jpg

The Attempt at a Solution



I figured that if the rope was cut, the resultant force would be = t in A B which is 7.31N, working out to an equation 7.31 = (25.3/9.80) * acceleration. However the answer is wrong. The question did not provide a numerical value for g so i was wondering if i shouldn't have used 9.80. Any help would be much appreciated thanks.
 

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ewnair said:

Homework Statement



3 blocks A B C are connected by strings as in attached image. The block C is descending with constant velocity. I've worked out the tension in string A B to be 7.31N. The coefficient of kinetic friction between each block and the surface is 0.36 and block a b weighs 20.3N each. I've also calculated the weight of C to be 25.3N. The last part of the question asked for the acceleration of block C if the rope between A B is cut.


Homework Equations



Link to figure

http://b.imagehost.org/view/0603/YF-05-56.jpg

The Attempt at a Solution



I figured that if the rope was cut, the resultant force would be = t in A B which is 7.31N, working out to an equation 7.31 = (25.3/9.80) * acceleration. However the answer is wrong. The question did not provide a numerical value for g so i was wondering if i shouldn't have used 9.80. Any help would be much appreciated thanks.
If the rope between A & B was cut, wouldn't the tension in AB be necessarily zero? Wouldn't the tension between BC be more relevant to the acceleration of C?
 
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