# Lowering an object without breaking the the rope

1. Oct 11, 2015

### Kingyou123

1. The problem statement, all variables and given/known data
How could a 1000 N object be lowered from a roof using a cord whose breaking strength is only 800 N?

2. Relevant equations
∑F=ma

3. 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?

Last edited: Oct 11, 2015
2. Oct 11, 2015

### TSny

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?

3. Oct 11, 2015

### Kingyou123

The two forces are weight and force tension. Where did I go wrong exactly?

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4. Oct 11, 2015

### TSny

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

Last edited: Oct 11, 2015