Roulette (curve) in this case, the point lies on the circle then the roulette is a cycloid. A related concept is a glissette, the curve described by a point attached to a given curve as it slides along two (or more) given curves. Formally speaking, the curves must be differentiable curves in the Euclidean plane. The "fixed curve" is kept invariant; the "rolling curve" is subjected to a continuous congruence transformation such that at all times the curves are tangent at a point of contact that moves with the same speed when taken along either curve (another way to express this constraint
What Is Life in the UK as perhaps the strongest of all of Harrison's singles. Writing in 1981, "NME" critic Bob Woffinden grouped "What Is LIfe" with "My Sweet Lord", "Isn't It a Pity" and "Awaiting on You All" as "all excellent songs". Reviewing the 2001 reissue of "All Things Must Pass", for "Rolling Stone", James Hunter wrote of how the album's music "exults in breezy rhythms", among which "the colorful revolutions of 'What Is Life' ... [move] like a Ferris wheel". The following year, in Rolling Stone Press's "Harrison" tribute book, David Fricke included "What Is Life" among his selection of "essential