How tall is the flagpole on the roof of the Factory?

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Homework Help Overview

The problem involves determining the height of a flagpole based on the dimensions of the pole and the length of a string wrapped around it. The flagpole is described as a cylinder with a specific diameter, and the string wraps around it a certain number of times before reaching the bottom.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants discuss various techniques for solving the problem, including the use of calculus and parametric equations to describe the string's path. Others suggest simpler methods, such as visualizing the unrolling of the flagpole and applying the Pythagorean theorem.

Discussion Status

There is an ongoing exploration of different methods to approach the problem, with some participants expressing the belief that simpler solutions exist. Multiple interpretations of the problem-solving techniques are being considered, but no consensus has been reached on a specific method.

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Participants emphasize the need for showing attempts to solve the problem and question whether the problem is appropriately placed in the forum based on its complexity.

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The flagpole on the roof of the Factory is 13 cm in diameter and a perfect cylinder. If one end of a 2300-cm-long string is attached to the top of the flagpole, and wraps around the flagpole exactly 16 times before ending at the bottom of the flagpole, how tall is the flagpole? Please round to the nearest centimetre, and submit only a number.
 
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You must show your attempt if you desire help. Have you tried the usual stuff like drawing a picture or looking at your notes for something relevant?
 
One technique that comes to mind is to find the equation(s) of the curve in space along which the string lies, and then find the arclength of that curve. This technique requires the use of calculus, which is probably inappropriate for a question posted in the Precalculus Math forum. On the other hand, newbies often post their questions to the wrong forum, so maybe this technique is applicable.

Assuming that's the case, the parametric equations for the curve that represents the string are
x = 6.5cos t
y = 6.5 sin t
z = Kt

where 0 <= t, and K is a constant that needs to be determined so that if the string is wrapped around the pole 16 times it reaches the top of the pole.
 
There is a much easier way to do this problem.
 
Avodyne said:
There is a much easier way to do this problem.

No kidding! That's exactly what I was thinking... :biggrin:
 
Avodyne said:
There is a much easier way to do this problem.
Well, hey, if your only tool is a hammer, everything looks like a nail!:biggrin:

An easier way would be to "unroll" the flagpole and see how far 1/16 of the string reaches. Did you have in mind something like this?
 
Draw the net of the flagpole, and where the string would be. You will need pythagorus theorem.
 

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