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## Homework Statement

The cable AB keeps the 8-kg collar A in place on the smooth bar CD. The y axis points upward. Determine the distance s from C to the collar A for which the tension in the cable is 150N.

location of:

B: (0m, 0.5m, 0.15m)

C: (0.4m, 0.3m, 0m)

D: (0.2m, 0m, 0.25m)

collar A's location is unknown. The required is the distance between C and collar A. The answer is 0.305m, but I need the solution for it.

For an easier look, http://img86.imageshack.us/img86/4710/392ij8.jpg" [Broken]

Someone answered this in yahoo answers. Can someone verify it?

http://answers.yahoo.com/question/index;_ylt=AgV3Ti6P9WnWMOA1BU8rsIDzy6IX?qid=20061225063557AANnWr1"

## Homework Equations

**e**dc= dc/|dc|

W=mg

**e**dc=eac

s=distance between A and C

## The Attempt at a Solution

DC=0.2i+0.3j-0.25k

**e**dc=0.4558i-0.6838j+0.5698k

I'm not sure about this part...

**e**ab=

__-Axi+(0.5-Ay)j+(0.15-Az)k__

sqrt(Ax^2+Ay^2+Az^2-Ay-0.3Az+0.2725)

**e**ac=

__(0.4-Ax)i+(0.3-Ay)j-Azk__

sqrt(Ax^2+Ay^2+Az^2-0.8Ax-0.6Ay+0.25)

s

**e**dc

**i**=-150eab

**i**

s

**e**dc

**j**=-150eab

**j**

s

**e**dc

**k**=-150eab

**k**

**e**ab

**i**=-Axi/|AB|

**e**ab

**j**=(0.5-Ay)j/|AB|

**e**ab

**k**=(0.15-Az)k/|AB|

I equated the "s" in the previous part and got...

Ay=0.5-1.5Ax

Az=1.25Ax+0.15

After that, my solutions just go in circles. I couldn't get what Ax is.

Also, Is my use of Ax, Ay, Az correct? I'm doubting about it.

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