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

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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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