Difference between revisions of "Talk:3176: Inverted Catenaries"
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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 <em>down?</em> And shouldn't such a "catenary fall" (if 3D objects) produce a flat-ish, unstable surface that would be [ahem] <em>very</em> interesting to drive (or walk or yada) on, and on which square tires would be useless? [[Special:Contributions/2605:59C8:160:DB08:216D:5149:ACEB:AD1C|2605:59C8:160:DB08:216D:5149:ACEB:AD1C]] 03:42, 4 December 2025 (UTC) | 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 <em>down?</em> And shouldn't such a "catenary fall" (if 3D objects) produce a flat-ish, unstable surface that would be [ahem] <em>very</em> interesting to drive (or walk or yada) on, and on which square tires would be useless? [[Special:Contributions/2605:59C8:160:DB08:216D:5149:ACEB:AD1C|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.--[[User:Trimutius|Trimutius]] ([[User talk:Trimutius|talk]]) 04:23, 4 December 2025 (UTC) | :Not necessarily. Depends on how catenary is weighted, it doesn't have to be of uniform density.--[[User:Trimutius|Trimutius]] ([[User talk:Trimutius|talk]]) 04:23, 4 December 2025 (UTC) | ||
| + | :If inverted catenaries flip, during their fall, then they become "inverted inverted catenaries", instead, which some ''might'' say are 'just catenaries' (or, indeed, be best observed as the catenary-chord, utmost). So, by ''definition'', they don't. ;) [[Special:Contributions/82.132.239.140|82.132.239.140]] 13:03, 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. | + | 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. {{unsigned ip|50.37.102.15|07:24, 4 December 2025}} |
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) | ||
| − | 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. | + | 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. {{unsigned ip|85.228.125.118|11:41, 4 December 2025}} |
Revision as of 13:03, 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)
- If inverted catenaries flip, during their fall, then they become "inverted inverted catenaries", instead, which some might say are 'just catenaries' (or, indeed, be best observed as the catenary-chord, utmost). So, by definition, they don't. ;) 82.132.239.140 13:03, 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. 50.37.102.15 (talk) 07:24, 4 December 2025 (please sign your comments with ~~~~)
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. 85.228.125.118 (talk) 11:41, 4 December 2025 (please sign your comments with ~~~~)
