Thread #2068722
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Can anyone tell me why shipping is more efficient than rail? I thought water has more friction than air
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square cube law or something idk but basically it's comparatively easy to move a thing through water as it gets bigger whereas on land it's a more linear relationship
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>>2068722
>water has more friction than air
ok you have a misconception here. the other poster is right in that a larger hull can carry more and do it more efficiently but i want to talk about what you typed here
water has more "friction", yes but a ship travels much slower than a train does. air resistance (and water resistance, liquids and gasses behave nearly exactly the same other than density and sometimes surface tension) losses increase incredibly fast the faster you are traveling. theres an exponent (of 4) in the formula. imagine this senario, you have a train going 10 meters per second, and has 1 resistance. now imagine that train travels 20 meters per second, how much resistance does it have? the speed doubles so surely its only 2 resistance right? no its actually 16. the air resistance is 16 times harder to overcome if you double the speed. i can explain the math more if you want but the simple explanation is explaining how exponents work. if i do 1x1x1x1 i get 1 right? now if i double the speed (or the 1s in this case) i get 2x2x2x2 which is 16. the math also works for all numbers, say i have 5x5x5x5 i get 625. if i double that to 10x10x10x10 i get 10000 (that divided by 625 is 16)
the faster you move the harder it is to keep moving at that speed. now imagine a train, how fast is it moving? probably 10x the speed of the boat right? so if the boat is moving at a speed of 1 and the train is moving at a speed of 10 we can use the exponent math from above to work out that the resistance. the boat has 1x1x1x1 resistance, which is 1. the train has 10x10x10x10 resistance, which is 10000. a shitload more, much more than the difficulty of traveling though water versus air
another thing to think about is rolling resistance. a train has this but a boat doesnt. you say that traveling though water is harder but didnt account for this (i dont know how to explain the math for this and im not bothered to do the comparison but i suspect this doesnt have a huge impact).
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>>2068722
Ships carry enormous amounts of cargo in the first place
They have a small power plant relative to their mass
The power plant is very thermally efficient (relative to other motive power plants)
Cargo ships seldom run at full throttle anyway, further reducing fuel consumption

Only a pipeline is more efficient but of course only a handful of commodities can be moved that way
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OP, these science shills are trying to gloss over it, but the answer is clear

Cargo ships are typically manned by Indians
And they're hardworkers, really
The very best

But talking about trains
We're looking at what, a 90% fatality rate?
Ban the technology, it's regressive

And let's bring in 100x cargo ship workers
Really, our economy can't survive without them
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>>2068738
>only a handful of commodities can be moved that way
we should liquefy the cows to make them easier to transport
slop for everyone
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a train like this carrying 20,000 containers would be 68 miles long
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>>2068748
>Posts a pic of some Indian train
What did he mean by this?
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>>2068748
That's an interesting thought. The train would probably need twenty or so locomotives and the ship would still comfortably out drag it.
Probably out stop it too.
:)
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>>2068722
Ships are really really big.
Like, imagine something super big like a really long train. But then like, a hundred times that.
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>>2068738
>Only a pipeline is more efficient but of course only a handful of commodities can be moved that way
bring back log flues
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>>2068731
good post
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>>2068748
thats just the first result for double stack container train on google image search
but we know who lives rent free in your head now
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>>2068731
back in the early days they realized that bicycle speed records could be shattered by removing the air resistance. pretty obvious now since every car has aerodynamic design and the whole point of bike racing teams is the plebs form a pack so the star teammate can draft them the whole time and save his energy for winning. but Major Taylor set a speed record drafting a locomotive, and motor-paced bike races were a thing for a while
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>>2068781
eh not really. i hit the character limit pretty early and didnt want to do a second post. i didnt get to talk about hills or expand on rolling resistance, all i could do was fix ops misconception about water = more resistance

>>2068783
>back in the early days
lol do you actually mean "back when physicists were respected + a few years to let everything catch up"?
>every car has an aerodynamic design
not really, every car is designed to sell. the areo differences between the average car today and the average car 40 years ago are smaller than you think. a truely areo car would be a waxed oval and would maybe get you an extra 20% fuel efficiency gain

and are you saying that drafting isnt minimising air resistance? the locomotive makes a lower pressure slipstream where the air is already moving the direction the bike would be pushing it, hard to explain in text but googling a diagram or a youtube video will make you get it fast. also drafting is incredibly dangerous because its practically unpredictable and any small bump can push you in a random direction at a pretty random speed. in other words im not surprised that the record was done on something using tracks and that motor vehicle drafting was only done for a short time lol
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>>2068789
>a truely areo car would be a waxed oval
Stop, stop, I can only get so erect.
You think (American) football shaped cars would be safer for pedestrians too?
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>>2068791
i doubt it, it might even be worse
probably the safest car design would be a car shorter than the average pedestrian and shaped something like an old timey train cowcatcher. probably sloped so that the long side is about 3 meters or so and made of foam. also seat belts would be banned and there would be spikes on the steering wheel that make the driver just as likely to die as the pedestrian
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>>2068782
Absolutely seething a day later
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>>2068789
>re you saying that drafting isnt minimising air resistance
no, you fucking autist, I was agreeing with you, just providing an anecdote. wtf is your problem
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>>2068722
S L O W. The most important lesson of this board.
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>>2068758
Wtf is that
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>>2068955
a river basically
back in the 1800s they used to float logs down rivers
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>>2068955
a direly needed feature/mechanic in hit vanilla-flavored transit simulator Timberborn
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>>2068956
>back in the 1800s they used to float logs down rivers

They still do that you dipshit!
https://youtu.be/zHakr6ASSBw?si=HRH90VXVqW6plEmY
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>>2069001
Language, anon! Rude!!
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>>2069005
I'm reporting you for being underage
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>>2068722
Freight trains can carry like ~300 TEUs in the US (less elsewhere). A single container ship like the Maersk triple-E is carrying 18,000 TEUs. Even smaller container ships have capacity in thousands of TEUs. Bulk freighters have the same advantage with loose material. You're just moving so much more shit and it never has to be pulled uphill.

>>2068956
>>2069001
Back in the 1800s, they would ship lumber internationally by building a boat out of the cargo and dissembling it when it reached it's destination. Britain was huge for this in the 1800s after they ran out of trees on the island.
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>>2068731
Where are you getting the power of 4? My understanding of drag is that it increases with the square of velocity. Even if you refer to the power required instead of the drag force itself, it only becomes the cube of velocity.
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>>2068722
Volume.
A lot of modern container ships haul the equivalent of 12,000 semi trucks.
They haul the equivalent of 24000 train cars. Planes can only fly 2 40 foot shipping containers or 2 semi trucks /4 train cars.
I hope this helps.
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>>2070795
No. Standard semi truck containers are 40 foot. A train car or container on a ship is 20feet so basically cut the ships capacity in half when converting to truck
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>>2070793
>They haul the equivalent of 24000 train cars.
Way too high of a figure. One well car platform holds 4 TEUs
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>>2070797
1 TEU: 20ft long, 8ft wide, 8.5ft tall
Moden mega class container ships haul 20k-24k TEU. Yes, twenty four thoused TEU. They are pretty amazing. They have been around for well over a decade.
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>>2070798
Yeah but a well car holds 4 TEU so you don't need 24,000 rail cars to move 24,000 TEU
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>>2070800
You are correct, my math was off. I thought a train car was 1 TEU but it is in fact 2 and if you can stack them, 4.
Still, the largest freight trains can only haul 400 TEU.
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>>2070801
>Still, the largest freight trains can only haul 400 TEU.
You're pretty retarded. A well car is about 50' long. It holds 4 TEUs. Maximum train length in my experience is about 12,000'. 10,000' is another shorter limit sometimes used.

So the actual TEU capacity of a train is in the 800-960 range. You're a huge faggot that is way too confident in your own line of reasoning. You've learned everything you know from wikipedia and youtube and it shows.
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>>2070805
You cant stack every box on a 6000 foot train or you will get derailment. My confidence comes from my vast knowledge of ships, shipping, and towing.
I hold a 200 ton masters license with a mate of towing.

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