Topic moved from General by dthead on 10 Oct 2016 21:40
  eddyb Chief Train Controller

due to air density and g force on the surface.


1. What is the density of air?- preferably in metric units.
2. What do you mean by g force on the surface? How is g force on the surface any different from g force a little underground? The symbol "g" is commonly used to denote acceleration due to gravity. Do you know and understand anything about Newton's Law of Gravitation?
Valvegear

1 The density of air (at sea level) is 1.225 kg/m3.


2 I only know what Wikipedia says about g force plus having a ride on a rollercoaster which would be a bit like doing 1,000kph on the surface or even a little under the surface.

Any train doing 1,000kph will need a sometimes very deep straight tunnel.

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  Valvegear Oliver Bullied, CME

Location: Richmond Vic
1. Thank you.

2. As I thought, you know nothing about it at all.
  eddyb Chief Train Controller

1. Thank you.

2. As I thought, you know nothing about it at all.
Valvegear
Please explain?
  justapassenger Minister for Railways

You can start with Newton's law of universal gravitation.

You will notice that the equation for gravitational force does not include any reference to an object's speed. A stationary object, a rollercoaster (relatively slow-moving) and a fast-moving object (e.g. the land speed record holding vehicle ThrustSSC moving at 1,227 km/h) all experience the same gravitational force.
  eddyb Chief Train Controller

You are referring to the gravitational pull between masses but I am talking about g force experienced by a sudden acceleration, braking or change of direction and I think most normal people would understand me.
  justapassenger Minister for Railways

Ah, so you are talking about acceleration, not a force of any type. Do try to be clearer.

The centripetal acceleration of an object following the curvature of the earth at 1,000 km/h is 0.012 m.s-2, or 0.0012g. That's an absolute non-issue.

If that is the same as the rollercoaster you went on, that would have been the most tame rollercoaster in the world or you were conned into being sold a ticket for a ride on something else which is not a rollercoaster. If it was the latter, I would urge you to contact the authority which governs consumer law in the location of that non-rollercoaster (e.g. NSW Fair Trading if it was in NSW) and seek their assistance with getting a refund for your ticket.
  Valvegear Oliver Bullied, CME

Location: Richmond Vic
For Eddy's benefit, there is an equation F =ma.

F = force
m = mass
a = acceleration.

"g force" is a piece of popular terminology which you have been using incorrectly for months.

justapassenger's post says it very well.
  eddyb Chief Train Controller

For Eddy's benefit, there is an equation F =ma.

F = force
m = mass
a = acceleration.

"g force" is a piece of popular terminology which you have been using incorrectly for months.

justapassenger's post says it very well.
"Valvegear"

OK
How would I say “A pilot experiences a varying degree of g force doing a loop the loop”
  Valvegear Oliver Bullied, CME

Location: Richmond Vic
Just leave out the "g".
  eddyb Chief Train Controller

Just leave out the "g".



"Valvegear"

These guys still think of g force and it may confuse them http://www.skyscrapercity.com/showthread.php?t=966040&page=4
  billybaxter Chief Commissioner

Location: Bosnia Park, Fairfield
I see Eddy's back to trying to impress us with technobabble again and being busted after about half a second. So, Eddy, you reckon this train  will be ten seats across. Does this mean the tunnel will be much wider than the NWRL tunnels, hence much more expensive to build, or that the seats will be tiny?
  eddyb Chief Train Controller

I see Eddy's back to trying to impress us with technobabble again and being busted after about half a second. So, Eddy, you reckon this train  will be ten seats across. Does this mean the tunnel will be much wider than the NWRL tunnels, hence much more expensive to build, or that the seats will be tiny?
"billybaxter"

No the tunnel will still be exactly the same 6m diameter with the train 5.6m allowing a wheelchair width aisle down the centre with 5 seats bigger than Sydney DD both sides.
  billybaxter Chief Commissioner

Location: Bosnia Park, Fairfield
How many trainsets are in your plan and where will the maintenance be done?
  eddyb Chief Train Controller

How many trainsets are in your plan and where will the maintenance be done?
billybaxter

There is very little maintenance with maglev and so it would be mainly cleaning and inspection and even though Albury and Canberra could do with the work I think it would be easier to have a spare set in a shunt at both Melbourne and Sydney.


With running costs so low it may be possible to maintain the schedule 24/7 so with three in stations three in tunnels and two being cleaned and checked it would total eight.
  justapassenger Minister for Railways

No the tunnel will still be exactly the same 6m diameter with the train 5.6m allowing a wheelchair width aisle down the centre with 5 seats bigger than Sydney DD both sides.
eddyb
Congratulations Eddy, seven lies in a post less than two lines long is a pretty impressive feat. Your $700 billion Magtube won't come off, but you might be in the running for a job helping Donald Trump run his Twitter account.
  eddyb Chief Train Controller

No the tunnel will still be exactly the same 6m diameter with the train 5.6m allowing a wheelchair width aisle down the centre with 5 seats bigger than Sydney DD both sides.
Congratulations Eddy, seven lies in a post less than two lines long is a pretty impressive feat. Your $700 billion Magtube won't come off, but you might be in the running for a job helping Donald Trump run his Twitter account.
justapassenger
Please tell me what you think I am lying about
  Valvegear Oliver Bullied, CME

Location: Richmond Vic
These guys still think of g force and it may confuse them
"eddyb"
Don't worry about it; they, and you, are already confused.
  Valvegear Oliver Bullied, CME

Location: Richmond Vic
No the tunnel will still be exactly the same 6m diameter with the train 5.6m allowing a wheelchair width aisle down the centre with 5 seats bigger than Sydney DD both sides.
"eddyb"
The maximum internal width of an A380 upper deck cabin is 5.80 metres, with 2 x 4 x 2 seating and two aisles.  Nobody is more than one seat from an aisle.
You want 5 x 5 and one aisle.  
Do you want to be:-
(a) the bloke in the aisle seat who will have 4 people clambering over him for toilet breaks, food etc
or
(b) the bloke in the outside seat who has to climb over four people to get to the aisle?
  billybaxter Chief Commissioner

Location: Bosnia Park, Fairfield
I've asked this one already Valvegear, Eddy said there'll be no toilets on the train so everybody can just 'hold it' till the next stop because they'll have plenty of time there. 4000 people rushing across an island platform, maybe a hundred of whom will want to use the toilet in the 15 minute stop. I don't think it's really the business class experience but Eddy reckons they won't care.
  Valvegear Oliver Bullied, CME

Location: Richmond Vic
Sorry, Billy; I missed it. However let's have this try and see if we get a better answer (don't hold your breath).
  billybaxter Chief Commissioner

Location: Bosnia Park, Fairfield
Eddy; how long will these 'shunts' be? With the length of the carriages you mentioned and only 20 cm clearance between them and the tunnel wall, there could be problems. You'll get the same problem at the island platforms at each station. You'll need two island platforms at Canberra and Albury as well. Where will the trains that do the Canberra to Albury section be cleaned and maintained?
  Valvegear Oliver Bullied, CME

Location: Richmond Vic
Eddy; do you seriously believe that Health Departments would allow these trains to be built without toilets? What do you expect the elderly, kids, and people who my have some form of illness to do?
  eddyb Chief Train Controller

OK it would be easy to whack a loo in each carriage if that is what you would like.


All trains would go the whole way with the cleaning and maintenance shunts either end in normal station atmosphere with enough room for these duties to be done and driven with a roadheader like all stations.


Melbourne and Sydney would have a platform either side as most passengers would come or go from there while Canberra and Albury would only have single island platforms but this should be ample as all trains would be in stations 15 minutes.


With capacity of 70,080,000 per year and only 10,000,000 per year travelling in ten years only in peak times would anybody have to climb over others like in the movies and if that bothered you could always go a bit earlier.
  billybaxter Chief Commissioner

Location: Bosnia Park, Fairfield
I thought it was three separate tubes. How can you get in passing loops at stations if the tubes are dead straight, as they'll have to be with your 20cm clearance? Is this a booked seat deal or turn up and go? How much time will be needed to go through security for what will be a magnet for terrorists and vandals?
  eddyb Chief Train Controller

I thought it was three separate tubes. How can you get in passing loops at stations if the tubes are dead straight, as they'll have to be with your 20cm clearance? Is this a booked seat deal or turn up and go? How much time will be needed to go through security for what will be a magnet for terrorists and vandals?
billybaxter

There would be double doors each side of the stations and their approaches to allow them be in normal atmospheric pressure and these sections would be driven wider with a roadheader to allow the train to turn.


Magtube carriages can be downloaded and scrutinised here https://3dwarehouse.sketchup.com/model/7040c0cd-1b84-4f9c-a1ff-de1795ee83eb/Magtube-train

We can only try our best to prevent idiots killing people and there is a risk in walking down the street.

If we stay in bed all day because of them they have won.

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