NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Angular inclination of an interstate highway
From: Jackson McDonald
Date: 2013 Dec 31, 19:06 +0000
From: FrankReed@HistoricalAtlas.com
To: jacksonmcdonald@hotmail.com
Date: Tue, 31 Dec 2013 10:28:19 -0800
Subject: [NavList] Angular inclination of an interstate highway
From: Jackson McDonald
Date: 2013 Dec 31, 19:06 +0000
OK guys, since I'm neither an engineer nor a math whiz (but rather a retired ambassador), it is with considerable trepidation that I propose:
arcmin = 3438 x 7/100 = 240.7 = 4 degrees
If that's not the correct answer, please refrain from giggling and provide the right response.
JMcD
From: FrankReed@HistoricalAtlas.com
To: jacksonmcdonald@hotmail.com
Date: Tue, 31 Dec 2013 10:28:19 -0800
Subject: [NavList] Angular inclination of an interstate highway
Here's a road sign from Google Street View imagery in southern Texas. According to someone who posted a similar image on flickr, this is the steepest incline on I-10, which runs across the southern US from Florida to California.
What is the angular inclination of this downhill slope in degrees (to the nearest tenth)? No calculator and no trig allowed. You can do it in your head with that magic number, 3438. Again: angles ARE ratios. We only quote them in degrees and minutes for historical continuity..
After you've done the calculation in your head, consider the possible trig solutions. Are they any better?
-FER
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: http://fer3.com/arc/m2.aspx?i=126062What is the angular inclination of this downhill slope in degrees (to the nearest tenth)? No calculator and no trig allowed. You can do it in your head with that magic number, 3438. Again: angles ARE ratios. We only quote them in degrees and minutes for historical continuity..
After you've done the calculation in your head, consider the possible trig solutions. Are they any better?
-FER
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