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A Rope, Two Telephone Poles... and Some Confounding Math

The Puzzler


RAY: There are two telephone poles. Each one is 100-feet tall. They are parallel and an unknown distance apart.

We're going to attach a 150-foot rope from the very top of one of the poles to the top of the other. This rope will, of course, droop down somewhat. That drooping rope is called a catanary, from the Latin word for chain.

The question is: What must be the distance between the two poles, so that the lowest point of the catanary is 25-feet above the ground?

Think you know? Drop Ray a note!

[ Car Talk Puzzler ]

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