Difference between revisions of "Talk:3176: Inverted Catenaries"
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Coming from a snowy country, we don't use all-season tyres. We have summer tyres (useless on snow and ice, very well suited for dry and wet surfaces) and winter tyres. Winter tyres without studs can legally be used all year round, but are ill-suited for summer conditions. [[Special:Contributions/109.247.36.180|109.247.36.180]] 08:32, 4 December 2025 (UTC) | Coming from a snowy country, we don't use all-season tyres. We have summer tyres (useless on snow and ice, very well suited for dry and wet surfaces) and winter tyres. Winter tyres without studs can legally be used all year round, but are ill-suited for summer conditions. [[Special:Contributions/109.247.36.180|109.247.36.180]] 08:32, 4 December 2025 (UTC) | ||
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| + | Although square wheels on inverted catenaries have no practical use, non-circular wheels on non-smooth tracks are used in rack railways, which are an application of a rack-and-pinion mechanism. | ||
Revision as of 11:41, 4 December 2025
Hoookay ... am I nutz, or shouldn't a physical object with the shape of an inverted catenary (2D or 3D) fall and land with the rounded side down? And shouldn't such a "catenary fall" (if 3D objects) produce a flat-ish, unstable surface that would be [ahem] very interesting to drive (or walk or yada) on, and on which square tires would be useless? 2605:59C8:160:DB08:216D:5149:ACEB:AD1C 03:42, 4 December 2025 (UTC)
- Not necessarily. Depends on how catenary is weighted, it doesn't have to be of uniform density.--Trimutius (talk) 04:23, 4 December 2025 (UTC)
A caternary curve is that of a tethered chain hanging loose in gravity, so defined as one with the curve pointed downward. this requires its inversion to curve up. Semantics, but in this case important ones.
Coming from a snowy country, we don't use all-season tyres. We have summer tyres (useless on snow and ice, very well suited for dry and wet surfaces) and winter tyres. Winter tyres without studs can legally be used all year round, but are ill-suited for summer conditions. 109.247.36.180 08:32, 4 December 2025 (UTC)
Although square wheels on inverted catenaries have no practical use, non-circular wheels on non-smooth tracks are used in rack railways, which are an application of a rack-and-pinion mechanism.
