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Highway and railroad curves are not circular arcs — they ... | funfact.wiki | funfact.wiki
Highway and railroad curves are not circular arcs — they use a special shape called a "clothoid" (Euler spiral). Its curvature changes gradually, so centrifugal force increases smoothly when transitioning from a straight section to a curve, rather than hitting suddenly.
  • Mathematics
  • Technology
  • Shape
  • Clothoid
  • Curve
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In the 1982 SAT, only 3 of 300,000 students answered a circle rotation problem correctly. Even the test makers were wrong, and the correct answer was not among the choices. The key is the coin rotation paradox: a circle rolling around an equal circle makes 2 full turns, not 1.
  • SAT
  • Mathematics
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