Wood Floats ......?
Discussion
Simpo Two said:
MBBlat said:
Basically the boat shaped hole in the water keeps the boat afloat, the hull of the boat just keeps the water out of this hole. Let the water in & the boat sinks
For metal yes, but the OPs question assumed it was 100% wood that was lighter than water. In that case, it will float even if holed. This equation leads to me to state that a boat carrying the OP as a captain would sink in a vat of Bromoform let alone water.
Asterix said:
Water - 1 litre = 1kg pretty much.
Very convenient
That's how the Frenchies designed it - 1cm3 weighing 1g at STP IIRC.Very convenient
Mind you a gallon of water weighs 10lb which is pretty easy too.
For a bunch of surrender monkeys Napoleon would be pretty pleased - equal biggest player in EU, metric system everywhere except US... not bad for a short dead bloke.
Having dived many wooden shhip wrecks I can confirm wooden boats do sink. Not only is it down to the type of wood but the "wooden" boats wood is never just wood when in boat form, at the very least its full of nails, coated in thick varnish, riddled with metal fittings to pump water in/out depending on the location and sealed together with any manner of different materials.
Wooden boats are composite constructions (like an F1 car :-) as such although the raw material might be very floaty the end result often isn't.
In fact many wooden boats are much "heavier" than ali, steel or plastic equivelent because of its limited strength you need lots of wood to do the job of lesser amounts of other materails.
Lastly (in my own personal experience) you need far more spares, tools and supplies on wooden boats because you spend so F**king long working on them compared to other materials its a mircale more of them don't sink! :-)
Wooden boats are composite constructions (like an F1 car :-) as such although the raw material might be very floaty the end result often isn't.
In fact many wooden boats are much "heavier" than ali, steel or plastic equivelent because of its limited strength you need lots of wood to do the job of lesser amounts of other materails.
Lastly (in my own personal experience) you need far more spares, tools and supplies on wooden boats because you spend so F**king long working on them compared to other materials its a mircale more of them don't sink! :-)
scubadude said:
In fact many wooden boats are much "heavier" than ali, steel or plastic equivelent because of its limited strength you need lots of wood to do the job of lesser amounts of other materails.
Although what makes the difference is the density of the material, not the amount.Perhaps in the Arctic you could use an ice boat
Simpo Two said:
scubadude said:
In fact many wooden boats are much "heavier" than ali, steel or plastic equivelent because of its limited strength you need lots of wood to do the job of lesser amounts of other materails.
Although what makes the difference is the density of the material, not the amount.Perhaps in the Arctic you could use an ice boat
http://en.wikipedia.org/wiki/Project_Habbakuk
MBBlat said:
Most people don't realise how heavy water is - a cubic meter of the stuff weighs around a tonne (1.0252 tonnes for seawater to be precise, 0.999 tonnes for fresh) so displacing it can support a lot of weight.
Maybe straying slightly OT, but with saline water being denser than fresh, after a period of calm weather, wouldn't the fresh congregate at and near the surface of the sea. Perhaps it is irrevocably mixed and inseparable?
Many woods tend to float with most of their mass underwater, like an iceberg, which means they are very close to the density of water and won't need much additional mass to drag them under.
I can understand the OP's question... a raft, for example, is more or less unsinkable.
I'd suspect that most wooden boats sink because they are (I think)
a) made of dense woods to keep the water out of the cabins and cargo holds etc, so they are not the most bouyant woods available.
b) treated with tar and other materials to keep them watertight and seal joins and stop it rotting etc, and these materials, being waterproof, are likely denser than water so do not float.
c) dragged down by all the other heavy stuff carried on board, not least the anchor but I also suspect that there is a lot of ballast in the bottom of the boat to stop it from capsizing, possibly a heavy metal rudder or simply lead ballast.
All of this means that a conventional wooden boat's overall density is greater than that of water (not including the volume of air it contains) so it floats on the displacement of water principle, i.e. it's the volume of air it contains that keeps the density down and keeps it afloat rather than the density of the wood itself. Also when bits break off, they do indeed float - or at least they do in pirate movies - just like a raft, so it must be all the heavy bits attached to the wood making it sink, not the wood itself.
I can understand the OP's question... a raft, for example, is more or less unsinkable.
I'd suspect that most wooden boats sink because they are (I think)
a) made of dense woods to keep the water out of the cabins and cargo holds etc, so they are not the most bouyant woods available.
b) treated with tar and other materials to keep them watertight and seal joins and stop it rotting etc, and these materials, being waterproof, are likely denser than water so do not float.
c) dragged down by all the other heavy stuff carried on board, not least the anchor but I also suspect that there is a lot of ballast in the bottom of the boat to stop it from capsizing, possibly a heavy metal rudder or simply lead ballast.
All of this means that a conventional wooden boat's overall density is greater than that of water (not including the volume of air it contains) so it floats on the displacement of water principle, i.e. it's the volume of air it contains that keeps the density down and keeps it afloat rather than the density of the wood itself. Also when bits break off, they do indeed float - or at least they do in pirate movies - just like a raft, so it must be all the heavy bits attached to the wood making it sink, not the wood itself.
fausTVR said:
MBBlat said:
Most people don't realise how heavy water is - a cubic meter of the stuff weighs around a tonne (1.0252 tonnes for seawater to be precise, 0.999 tonnes for fresh) so displacing it can support a lot of weight.
Maybe straying slightly OT, but with saline water being denser than fresh, after a period of calm weather, wouldn't the fresh congregate at and near the surface of the sea. Perhaps it is irrevocably mixed and inseparable?
And thermohaline cirrculation drives the north Atlantic drift, using differentials in heat and density due to salt loading (the temp means a density difference too) to convey heat from the gulf of Mexico to the UK. We have this to thank for the UK's abnormally warm climate given its latitude.
It's all about relative density.
Which is why quicksand isn't as dangerous as films would have you believe, all you have to do is move your limbs and you go straight to the top. Shouldn't jump into oil though.
If the overall density of the boat and its contents is less than that of the water, it will float no matter what shape, how many holes are in it or which way up it is.
This is how submarines work after all, their overall density is greater than water, until they increase the amount of uncompressed air in their ballast tanks so their overall density is lower than the water.
http://express.howstuffworks.com/express-submarine...
Which is why quicksand isn't as dangerous as films would have you believe, all you have to do is move your limbs and you go straight to the top. Shouldn't jump into oil though.
If the overall density of the boat and its contents is less than that of the water, it will float no matter what shape, how many holes are in it or which way up it is.
This is how submarines work after all, their overall density is greater than water, until they increase the amount of uncompressed air in their ballast tanks so their overall density is lower than the water.
http://express.howstuffworks.com/express-submarine...
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