Lowering an object without breaking the the rope

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Homework Statement


How could a 1000 N object be lowered from a roof using a cord whose breaking strength is only 800 N?

Homework Equations


∑F=ma

The Attempt at a Solution


By slowing down the acceleration to a point where the force down would be less than 800.
weight=m(g)
1000N=m(9.8)
102.04kg=m
∑F=ma
799.99=102.04kg(a)
7.84m/s^2=a
Would this be the right answer?
 
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This is not the correct answer. Be sure to draw a free body diagram of the object. How many forces act on the object as it is being lowered?
 
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TSny said:
This is not the correct answer. Be sure to draw a free body diagram of the object. How many forces act on the object as it is being lowered?
The two forces are weight and force tension. Where did I go wrong exactly?
 

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Diagram looks good. When you set up ∑F = ma, the left side represents the vector sum of the two forces.
 
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