Cylinder problem:restriction on the height if the radious

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Homework Help Overview

The problem involves a cylindrical frame constructed from a fixed length of wire, with specific conditions on the radius and height of the cylinder. Participants are tasked with deriving an expression for the radius in terms of height and determining restrictions based on given dimensions.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to derive a formula for the radius based on the height and the total wire length. They express confusion regarding the implications of a minimum radius requirement and how it affects the height.

Discussion Status

Participants are actively engaging with the problem, questioning the units of measurement for the radius and clarifying the conversion from centimeters to meters. There is an indication of a potential error in the original poster's inequality setup, prompting further discussion.

Contextual Notes

There is a need to clarify the units of measurement for the radius, as well as the implications of the minimum radius requirement on the height of the cylinder. The original poster's calculations are based on a specific interpretation of the problem constraints.

Aoiro
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A cylindrical frame consisting of three circles and four vertical supports is built from 6m of wire, as shown. The frame is then covered with paper to form a closed cylinder.
1. Determine an expression for the radius r in terms of the height h.
2. determine the restriction on the height if the radious of the cylendar must be atleast 10.
I got the first one;
1.r=3-2h/3pi
But I did not get the second one
2.
10 > 3- 2h/3pi

3pi(10)> 3- 2h

30pi-3 > -2h

(30pi - 3)/-2 < h

Can someone help me? Thanks
 
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A good question would be 10 what? m? Miles? pounds?

Recall that the length of the wire is given in meters, so if you try to make a 10m diameter circle you will have troubles.
 
^ sorry, 10cm
 
You need to use 10cm=0.1m, as you used 6m initially. Also, I think your < is the wrong way round.
 
^ thank you
 

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