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Effect of weight on boat speed |
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423zero
Really should get out more Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3406 |
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Topic: Effect of weight on boat speed Posted: 05 Nov 20 at 6:42pm |
https://en.m.wikipedia.org/wiki/Buoyancy
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Robert
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423zero
Really should get out more Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3406 |
Post Options Quote Reply Posted: 05 Nov 20 at 6:33pm |
https://en.m.wikipedia.org/wiki/Displacement_(fluid)
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Robert
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Sam.Spoons
Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3398 |
Post Options Quote Reply Posted: 05 Nov 20 at 6:28pm |
In the light it certainly does but so when the wind picks up the lighter 'crew' is at a disadvantage. I suspect that at clubs where such practice is common they will have a lower PN to apply when the helm is sailing alone. OTOH would it be fair to give a couple of 50kg teens the straight PN handicap while penalising a 100kg adult for sailing alone?
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Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
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Sam.Spoons
Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3398 |
Post Options Quote Reply Posted: 05 Nov 20 at 6:23pm |
The second paragraph is wrong for starters "The object pushes out a volume of water that is equal to its own volume." that is only true for an object that sinks. For an object to float it must displace less than it's volume of water.
They go on to qualify but it's all a bit 'lies to children'...
Edited by Sam.Spoons - 05 Nov 20 at 6:24pm |
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Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
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epicfail
Groupie Joined: 01 Dec 19 Online Status: Offline Posts: 61 |
Post Options Quote Reply Posted: 05 Nov 20 at 6:21pm |
Maybe slightly off topic but.. We get some double handers doing handicap racing being sailed singlehanded - normally in light to moderate conditions. Assuming that the PY is based on these classes being sailed by two people - removing the weight of an average adult must have a significant impact on boat speed.
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423zero
Really should get out more Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3406 |
Post Options Quote Reply Posted: 05 Nov 20 at 6:08pm |
https://www.britannica.com/video/181395/Discussion-forces-bodies-water#:~:text=When%20an%20object%20enters%20water,This%20is%20called%20displacement.
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Robert
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423zero
Really should get out more Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3406 |
Post Options Quote Reply Posted: 05 Nov 20 at 6:05pm |
They are full of foam.
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Robert
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Sam.Spoons
Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3398 |
Post Options Quote Reply Posted: 05 Nov 20 at 5:58pm |
Windsurfers float and most don't have air space inside
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Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
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423zero
Really should get out more Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3406 |
Post Options Quote Reply Posted: 05 Nov 20 at 3:00pm |
Plus it's less dense due to air space in Hull.
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Robert
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Sam.Spoons
Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3398 |
Post Options Quote Reply Posted: 05 Nov 20 at 2:39pm |
Perhaps I should have said "when a boat floats it displaces exactly the same weight of water as it weighs"?
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Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
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