Cycloid - Arc Length

Arc Length

The arc length S of one arch is given by

\begin{align} S &= \int_{t=0}^{t=2 \pi} \left^\frac{1}{2} dt \\ &= \int_{t=0}^{t=2 \pi} r \sqrt{2 - 2\cos(t)} dt \\ &= \int_{t=0}^{t=2 \pi} 2r \sin\left(\frac{t}{2}\right) dt \\ &= 8 r
\end{align}

Read more about this topic:  Cycloid

Famous quotes containing the words arc and/or length:

    You say that you are my judge; I do not know if you are; but take good heed not to judge me ill, because you would put yourself in great peril.
    —Joan Of Arc (c.1412–1431)

    And my spirit is grown to a lordly great compass within,
    That the length and the breadth and the sweep of the marshes of
    Glynn
    Will work me no fear like the fear they have wrought me of yore
    When length was failure, and when breadth was but bitterness sore,
    And when terror and shrinking and dreary unnamable pain
    Drew over me out of the merciless miles of the plain,—
    Oh, now, unafraid, I am fain to face
    The vast sweet visage of space.
    Sidney Lanier (1842–1881)