Environment & Energy

tclambert

(11,187 posts)

36. To allow 4,000 mph, the tube has to have the air sucked out.

Thu Jul 18, 2013, 03:23 PM

Jul 2013

A vacuum tube!

You have to remove the air because 4,000 mph is about 5 times the speed of sound. (Sonic booms in a tube? Not pleasant.) Plus you'd have problems with air pressure differentials ahead of and behind the capsule. So, if it breaks down and you get stuck halfway, hold your breath till help help comes.

To get to 4,000 mph in a six minute trip, 3 minutes of acceleration, 3 minutes of deceleration, you'd need 1 g acceleration and 1 g deceleration. That's way more than the typical airliner.

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LA to SF in 6 minutes? Meet Elon Musk's 4,000 mph transportation concept, the "Hyperloop" [View all] wtmusic Jul 2013 OP

If you enjoy MRI's pscot Jul 2013 #1

How so. Not being snarky, but to get to the "science" behind truedelphi Jul 2013 #2

Just going by the picture pscot Jul 2013 #5

“It’s a cross between a Concord, a rail gun and an air hockey table,” PoliticAverse Jul 2013 #31

To allow 4,000 mph, the tube has to have the air sucked out. tclambert Jul 2013 #36

My summer job right after HS was on the 9th floor of truedelphi Jul 2013 #37

There's an express elevator to the observation deck of the Sears Tower.... Spitfire of ATJ Jul 2013 #44

That sounds like fun. truedelphi Jul 2013 #47

Santa Ana winds in the Wells Fargo building in LA are the worse... Spitfire of ATJ Jul 2013 #50

To get between those two points in an hour, I could totally endure that. AtheistCrusader Jul 2013 #3

Would not want to be in that thing during an earthquake n/t n2doc Jul 2013 #4

Is it bullet proof? hunter Jul 2013 #6

It would have to be, wouldn't it. wtmusic Jul 2013 #9

Considering it would move at twice the muzzle velocity of a typical .30-06 bullet . . . tclambert Jul 2013 #38

Why couldn't we be happy making something feasible that went 500 MPH? NoOneMan Jul 2013 #7

I'm happy at 35mph. hunter Jul 2013 #12

+1. Agree 100% Starboard Tack Jul 2013 #22

And I'm happy walking NoOneMan Jul 2013 #51

Did you read this book? concreteblue Jul 2013 #53

No, I haven't. Looks interesting. hunter Jul 2013 #55

Sometimes you need face to face interaction One_Life_To_Give Jul 2013 #57

Which global "experts?" hunter Jul 2013 #59

IEC One_Life_To_Give Jul 2013 #60

the carbon car is close SCantiGOP Jul 2013 #28

They're on sale muriel_volestrangler Jul 2013 #49

sounds like more of a Shelbyville idea n/t Enrique Jul 2013 #8

+1 Fearless Jul 2013 #21

Hey! Is that fast enough for a little relativity? Benton D Struckcheon Jul 2013 #10

Naw, time dilation effects aren't relevant until much higher speeds. joshcryer Jul 2013 #13

Well, that should help save the planet. Starboard Tack Jul 2013 #11

Hands across the water, heads across the sky. hunter Jul 2013 #14

Just fyi, about 6.5 million passengers take LA to SF commercial flights in a year Bluenorthwest Jul 2013 #16

Did I claim that LA to SF commuters were billionaires? Right, I thought not. Starboard Tack Jul 2013 #20

You haven't thought this through, have you? kristopher Jul 2013 #40

Wow! Sorry if I gave that impression. Starboard Tack Jul 2013 #48

Sure, we can't even get the Acela to 100 mph for more than, what, 20% of its route . . . hatrack Jul 2013 #15

Boys and their toys. GliderGuider Jul 2013 #17

Since this will need to be built from scratch OKIsItJustMe Jul 2013 #18

I like that madokie Jul 2013 #23

At 559 km between LA and SF and 100 Kph, that's five and a half hours. Thor_MN Jul 2013 #27

"if the roads were not filled with cars" OKIsItJustMe Jul 2013 #29

The comparison is between 4000 mph and 60 mph Thor_MN Jul 2013 #32

Who needs to travel at 4000 MPH!? OKIsItJustMe Jul 2013 #33

Really? For the same reason we don't travel by wagon train. Thor_MN Jul 2013 #35

I didn’t propose taking the SkyTran from New York to LA OKIsItJustMe Jul 2013 #39

I think you are hung up on local travel, i.e. off topic. Thor_MN Jul 2013 #41

My point was, as a society, I believe the SkyTran to be a better investment than the hyperloop OKIsItJustMe Jul 2013 #42

You are certainly free in your belief. Thor_MN Jul 2013 #43

I'd hate to be in this when the power fails OnlinePoker Jul 2013 #62

I suppose they wouldn’t plan for something like that… OKIsItJustMe Jul 2013 #63

If you don't mind being crushed One_Life_To_Give Jul 2013 #19

Why couldn't you have seats on a gimbal? Thor_MN Jul 2013 #24

That is only one minor piece One_Life_To_Give Jul 2013 #58

How do make it through the day so worried about things for which you are not responsible? Thor_MN Jul 2013 #61

Good observation. wtmusic Jul 2013 #25

Lets test it on Rush and Hannity. bravenak Jul 2013 #26

Hilarious, also, a great idea. n/t Benton D Struckcheon Jul 2013 #30

Rush's fat ass would plug the tube NickB79 Jul 2013 #34

I'm goin' to San Fransisco.... Spitfire of ATJ Jul 2013 #45

Well if he wants to route it through the Peninsula, he's SOL. Starry Messenger Jul 2013 #46

The basic technology to do this already exists jmowreader Jul 2013 #52

While I find this interesting... Javaman Jul 2013 #54

working prototype Locrian Jul 2013 #56