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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Surveying problem
From: David Pike
Date: 2021 Feb 25, 01:07 -0800
From: David Pike
Date: 2021 Feb 25, 01:07 -0800
Marty. I just checked. There really is only about 1.5 inches difference between 30ft of 100ft radius arc and its chord. From my diagram and working:
Chord CB = 2x100sin17.31°/2 = 200sin8.655° = 30.097ft compared to an arc of
17.31/360 x 2 x 100 x 3.142 = 30.216 = 0.119ft or 1.428inches. That's just 5mm more than the diameter of one old UK bronze penny. Isn’t that amazing!
Next Question. How much money could you make by organising a ‘Mile of Pennies’ charity event in the 1950s? 240 old UK pennies = one UK £. DaveP