Edition
-202403121604.gif)
Boats for sale
| Laurent Giles 'Jolly Boat' Exeter |
 |
| J24 (Sail No. 4239) Dartmouth |
 |
| Laser XD 203301 Upminster |
 |
List classes of boat for sale |
Effect of weight on boat speed |
Post Reply 
|
Page <1 2345> |
| Author |
 Share Topic Printable Version Delicious Digg Facebook Furl Google MySpace Newsvine reddit StumbleUpon Translate Twitter Windows Live Yahoo Bookmarks Topic Search  Topic Options
|
423zero 
Really should get out more 
Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3406 |
 Post Options
 Quote Reply
 Topic: Effect of weight on boat speedPosted: 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.
|
|
|
Robert
|
|
 |
|
|
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.
|
|
|
|
|
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 |
|
|
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
|
|
|
|
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?
|
|
|
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
|
|
|
|
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)
|
|
|
Robert
|
|
|
|
|
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 6:42pm |
|
https://en.m.wikipedia.org/wiki/Buoyancy
|
|
|
Robert
|
|
|
|
|
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 6:48pm |
|
Yup, that's pretty much what I was saying.
|
|
|
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
|
|
|
|
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 6:49pm |
|
More specific to why ships float
https://letstalkscience.ca/educational-resources/stem-in-context/why-do-ships-float |
|
|
Robert
|
|
|
|
|
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 6:58pm |
|
That's wrong too..... It says
How does buoyancy relate to density?If a block of wood measuring one cubic centimeter (1 cm x 1 cm x 1 cm) is placed in a container of water, the amount of water displaced will equal the weight of the block of wood. But what about if a block of the same size is made of lead? Lead has a much higher density than wood. If a one cubic centimeter block of lead is placed in a container of water, the amount of water displaced will equal the weight of the block of lead. The amount of water displaced by the block of lead (weighing 11.34g) will be exactly 1cc and will weigh 1g, so it will equal the volume of the block of lead but not it's weight |
|
|
Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
|
|
|
|
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 7:05pm |
|
I think they mean, the amount of air (buoyancy) to weight of object, to make it float, ie you will need more air (buoyancy) for lead to float than wood.
|
|
|
Robert
|
|
|
|
|
Post Reply
|
Page <1 2345> |
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
Bulletin Board Software by Web Wiz Forums® version 9.665y
Copyright ©2001-2010 Web Wiz
Change your personal settings, or read our privacy policy
Copyright ©2001-2010 Web Wiz
Change your personal settings, or read our privacy policy