(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Essentially there is a power line which must be strung between posts on two mountains which are 1669.602m apart.

The first mountain is 5m higher than the second.

To overcome tension the wire is strung with a sag, 1m of sag for every 75m, or part thereof. This sag is relative to the lower pylon.

Determine an equation for the profile of the wire between the two mountains, if the arc is to be in a PARABOLIC shape.

2. Relevant equations

I've worked out that 1669.602/75 = (22. something) which means there must be 23m of sag, as it states part thereof. Relative to the lower pylon, I understand this to mean the turning point will be 23m below the smaller mountain.

Due to the difference in heights, this is obviously not a symmetrical parabola.

3. The attempt at a solution

I've tried letting the turning point be the origin, and having 3 points

(X2 - 1669.602 , 28)

(1669.602-X1, 23)

(0,0)

where x2 is the distance from the turning point to the second mountain, and X1 is the distance between the first mountain to the turning point.

I've also tried letting the first mountain be the origin, with 3 points

(0,0)

(???,-28) - minimum point

(1669.602,-5)

But I'm very stuck on what to do with these possible points. Please help.

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# Homework Help: Parabola problem - some data given.

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