I’ve got a 150 cm of measurement tape. So to diagnose 1° of sin limit & tan limit as well as 1° of Phew arc length, I set r = 8000 cm.
The description of 1° diagram is as follows:
Neck length = 1-cos1 = 1.2 cm
Tan limit = 2tan(1:2) = 139.6 cm
Sin limit = 2sin(1:2) = 139.6 cm
Phew’s 1° of arc length = 140.9 cm
You may say Tan limit is bigger than Pi’s arc length. Nice try, but what you measure is a straight line, or chord ~ NOT arc.
With the neck’s length = 1.2 cm, both tan limit & sin limit = 139.6 cm, and Phew’s arc length = 140.9 cm… Does Phew’s arc length make sense???
WHO SAYS NO? 🤣✌️





