Cycloid Calculator
Find the arc length and area of one cycloid arch.
A cycloid is the path traced by a point on a rolling circle's rim.
The math behind it
One arch has length 8r, encloses area 3πr², and spans a width of 2πr (one full rotation).
Worked example
Radius 2 → arch length 16, area ≈ 37.70.
FAQ
Why is the area exactly 3 circles?
The area under one arch equals three times the rolling circle's area — a classic result of Galileo and Roberval.