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Re: Vernier explanation
From: Lars Bergman
Date: 2022 Jun 30, 05:21 -0700
From: Lars Bergman
Date: 2022 Jun 30, 05:21 -0700
Tony asked "What exactly is the shape of that "magnifying curve"?". Call the vertical height between the upper and lower scales h.
Then y=h·(90°-arcsin(x))/20°. This gives (almost) equidistant degree marks on the curved segment.
x y angle
0.940 h 70°
0.966 3·h/4 75°
0.985 h/2 80°
0.996 h/4 85°
1 0 90°
Lars
