- #1

Ascendant78

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## Homework Statement

A 60kg student lowers herself down 40m at a constant speed of 1.0 m/s. The chair has a mass of 35kg. Find the force of the rope. (See image)

## Homework Equations

I was using force equations in attempts to solve for the problem.

## The Attempt at a Solution

F

_{chair}+F

_{student}-F

_{rope}-F

_{rope}=m(a)

35(9.8)+60(9.8)-2F

_{rope}=95(0)

343+588-2F

_{rope}=0

2F

_{rope}=931

F

_{rope}=

**465.5N**

Although the answer I got above was 465.5N, the answer listed in the back of the book was F

_{rope}=

**490N**. I am at a complete loss as to what I am doing wrong here? I did a similar problem where the person was traveling upwards like this at a constant velocity and got it right. Not sure what changed here that I am not taking into consideration?

I am also curious after having done a similar problem, since the force is split into 2 parts, the force quantity for the rope would be the value for each rope individually, correct (one attached to chair and the one held by the student)? I just want to make sure I am understanding this correctly. Also, if that is the case, then if I were asked what the total force being applied to the rope was, it would be double the value to account for each side being pulled, correct?

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