4 ms·

I live in "the West" but English isn't my main language. I have no idea what a conoid is.

• rovr138 2y ago
  > A conoid is a ruled surface whose rulings are parallel to a plane (called the directrix plane) and intersect a fixed line (called the axis of the conoid) (Gellert et al. 1989, p. 202). Examples include the circular conoid, helicoid, hyperbolic paraboloid, parabolic conoid, Plücker conoid, right circular conoid, Wallis's conical edge, Whitney umbrella, and Zindler conoid. If the axis is perpendicular to the directrix plane, the conoid is called a right conoid (Gray et al. 2006, p. 436). https://mathworld.wolfram.com/Conoid.html https://mathworld.wolfram.com/Conoid.html so, a surface with stripes - example https://pxhere.com/en/photo/1366651 https://pxhere.com/en/photo/1366651
  • happymellon 2y ago
    This doesn't look like a surface with stripes at all. > https://en.m.wikipedia.org/wiki/Whitney_umbrella https://en.m.wikipedia.org/wiki/Whitney_umbrella
  • cmrx64 2y ago
    Where did you get stripes from in any of that? A surface is ruled when it can be constructed by extruding a line (or segment) along some path… like waving a ruler around.
    • radicality 2y ago
      I think they meant that something striped and rectangular, like a crosswalk, is a 'ruled surface' because the stripes themselves are like the ruler ? So I guess a crosswalk (flat rectangle in 3D space), would be considered a 'ruled surface', but I don't think it meets the other requirement to make it a conoid.
• BenjiWiebe 2y ago
  I live in the US, English is my only language. I could probably guess what a conoid is, but I don't actually know (until reading these comments).