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Re: ebbco sextant
From: David Pike
Date: 2015 Jan 1, 10:04 -0800
From: David Pike
Date: 2015 Jan 1, 10:04 -0800
Greg. I’m not sure what you’re calling O, position of the observer or centre of the circle? I’ve used O is the centre of the circle. Using my diagram, ‘Some people have’, so Sin=Perp/Hyp. Therefore Sin(AOB/2) = (½ AB)/R . Shouldn’t it be R = (1/2AB)/Sin (AOB/2) or R = (1/2AB)/Sin APB? Silly question, but with no protractor, or compass rose and parallel rule, how do you get the value of angle APB in order to find the sine of it? Dave
