What-if 0064: "Rising Steadily"

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What-if 0064: "Rising Steadily"

Postby Eutychus » Tue Sep 24, 2013 8:14 am UTC

Rising steadily
If you suddenly began rising steadily at one foot per second, how exactly would you die? Would you freeze or suffocate first? Or something else?

Rebecca B


I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.
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Re: What-if 0064: "Rising Steadily"

Postby Quicksilver » Tue Sep 24, 2013 8:16 am UTC

"So there's that" immediately made me think of Breaking Bad.

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Re: What-if 0064: "Rising Steadily"

Postby rhomboidal » Tue Sep 24, 2013 8:24 am UTC

I'm confused -- does the Death Zone come before or after the Post-Tribulation and Last Judgment?

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Re: What-if 0064: "Rising Steadily"

Postby Sandor » Tue Sep 24, 2013 9:27 am UTC

Eutychus wrote:I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.

I suspect this is talking more about height-above-ground is than it is height-above-sea-level.

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Re: What-if 0064: "Rising Steadily"

Postby Patrik3 » Tue Sep 24, 2013 10:27 am UTC

It would take you 5-7 seconds to rise out of arms' reach, depending how tall your friends are.


... you don't say. This 'fact' made me laugh because I read it first assuming that there were some complicated mathematics or research behind this assertion - as in the rest of "What-If" - but then after a moment I realized how obvious the statement actually was.

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Re: What-if 0064: "Rising Steadily"

Postby Envelope Generator » Tue Sep 24, 2013 10:53 am UTC

rhomboidal wrote:I'm confused -- does the Death Zone come before or after the Post-Tribulation and Last Judgment?


It's just before Girl We Couldn't Be Much Higher.
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Re: What-if 0064: "Rising Steadily"

Postby Klear » Tue Sep 24, 2013 10:59 am UTC

Envelope Generator wrote:
rhomboidal wrote:I'm confused -- does the Death Zone come before or after the Post-Tribulation and Last Judgment?


It's just before Girl We Couldn't Be Much Higher.


Get Much Higher. But anyway, I suspect you'll have trouble lighting fires at such altitude.

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Re: What-if 0064: "Rising Steadily"

Postby dalcde » Tue Sep 24, 2013 11:03 am UTC

Eutychus wrote:I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.


I guess if there's nothing around the wind becomes a problem

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Re: What-if 0064: "Rising Steadily"

Postby DanD » Tue Sep 24, 2013 11:04 am UTC

Eutychus wrote:I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.


At or near the equator, the (climatic) snow line seems to be around 4-5km, and then falling once you get past the tropics. So Randal might be basing this on a more northerly latitude. Or, and I don't really have much to back this up, solar heating of the ground and possibly anabatic winds might combine to warm the atmosphere near the earth even at altitude in a way that doesn't happen in free air.

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Re: What-if 0064: "Rising Steadily"

Postby Lazy Tommy » Tue Sep 24, 2013 11:15 am UTC

Eutychus wrote:I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.


It may not be freezing in Quito, but its average daytime high is a full 10°C cooler than that of the coastal city of Manta, also in Ecuador and also less than 1° from the equator. When you're travelling in mountainous terrain, the difference in temperature due to altitude is very noticeable.

I'm guessing Randall's reference point is the Northeastern U.S., both because that's where he lives and because of the Empire State Building reference.

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Re: What-if 0064: "Rising Steadily"

Postby cellocgw » Tue Sep 24, 2013 12:09 pm UTC

GLR forgot to mention the excellent view you'd get, at least until you passed out. If you start out somewhere near the equator, you should be able to watch a few time zone's worth of ground go by as you rise. Well, actually you'd see time zones go by no matter where you started, but it wouldn't be much in the way of linear excursion near the poles.

Plus you'd escape the Zanclean Flood.
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Re: What-if 0064: "Rising Steadily"

Postby FrobozzWizard » Tue Sep 24, 2013 12:39 pm UTC

River Tam has let me down with her calm assurance that we'd freeze to death before asphyxiating!

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Re: What-if 0064: "Rising Steadily"

Postby JBJ » Tue Sep 24, 2013 12:43 pm UTC

DanD wrote:
Eutychus wrote:I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.


At or near the equator, the (climatic) snow line seems to be around 4-5km, and then falling once you get past the tropics. So Randal might be basing this on a more northerly latitude. Or, and I don't really have much to back this up, solar heating of the ground and possibly anabatic winds might combine to warm the atmosphere near the earth even at altitude in a way that doesn't happen in free air.

Even in a more northern latitude, the temperature aloft at 2km (or around 6,500ft) is going to be between 5-10C as of today in the Boston/New York area. However, that's the actual air temperature whereas Randall mentions wind chill. The winds at that height will vary a lot, but again as of today, they are between 20-30 knots (today's values taken from NOAA Aviation Weather Center). Taking the lowest temp and highest wind speed, that gives a wind chill of about -1.6C, so it would feel like it is just below freezing (but not by much). Even though it feels freezing, frostbite is not yet a concern. Hypothermia, yes. Frostbite, no.
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Re: What-if 0064: "Rising Steadily"

Postby Dr. Diaphanous » Tue Sep 24, 2013 1:13 pm UTC

What would happen to a chilled human corpse passing through the upper atmosphere and orbital space?

She'd take 3.8 days to get into space (~100 km) and 3.8 years to pass geosynchronous orbit (35 786 km).

I think she'd freeze in the upper troposphere and thaw and re-freeze passing through the stratosphere and mesosphere.

Once in space one side of her will be exposed to the full force to the sun except when she's in the Earth's shadow. I'm guessing that if she's spinning even a bit she'll get pretty hot on both sides and her moisture will all evaporate. I guess the desiccated corpse will then be broken down by solar and cosmic radiation.

Any idea if what I said is right or of how the corpse would be affected by the radiation?
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Re: What-if 0064: "Rising Steadily"

Postby davidstarlingm » Tue Sep 24, 2013 1:17 pm UTC

dalcde wrote:
Eutychus wrote:I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.


I guess if there's nothing around the wind becomes a problem

Eutychus wrote:Rising steadily
If you suddenly began rising steadily at one foot per second, how exactly would you die? Would you freeze or suffocate first? Or something else?

Rebecca B


I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.

Randall used a reference point near sea level because the ground heats the air above it. Even if it's not a particularly sunny day, there's enough light being absorbed by the ground and radiated up into the air that the air at ground level stays toasty.

So air temperature isn't just a function of altitude; it's also a function of how far you are from the big solar reflector called Earth.

Dr. Diaphanous wrote:I guess the desiccated corpse will then be broken down by solar and cosmic radiation.

Any idea if what I said is right or of how the corpse would be affected by the radiation?

Unless she's traveling in the general direction of the sun, I doubt solar radiation will do much. Cosmic radiation certainly won't be enough to do anything.

She'll be very horribly sunburned very fast, but since she's dead, there won't be any fluid moving around to produce blisters and so forth.

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Re: What-if 0064: "Rising Steadily"

Postby jozwa » Tue Sep 24, 2013 2:09 pm UTC

"So long, suckers!"

That made me laugh.

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Re: What-if 0064: "Rising Steadily"

Postby rmsgrey » Tue Sep 24, 2013 2:59 pm UTC

I think not enough attention has been given to the question of what "up" means here - if your only motion relative to the ground is a steady 1 foot per second directly away from the Earth's centre of gravity (a forced geosynchronous orbit with steadily increasing radius) then you'd exceed the speed of light before leaving the solar system (if you started on the equator, then you'd hit light speed somewhere between Uranus and Neptune's orbits). Other simple movement schemes would tend to do things like have you (try to) pass through a nearby wall, so you'd be bludgeoned to death before you had time to asphyxiate...

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Re: What-if 0064: "Rising Steadily"

Postby cellocgw » Tue Sep 24, 2013 3:22 pm UTC

rmsgrey wrote:I think not enough attention has been given to the question of what "up" means here - if your only motion relative to the ground is a steady 1 foot per second directly away from the Earth's centre of gravity (a forced geosynchronous orbit with steadily increasing radius) then you'd exceed the speed of light before leaving the solar system (if you started on the equator, then you'd hit light speed somewhere between Uranus and Neptune's orbits). Other simple movement schemes would tend to do things like have you (try to) pass through a nearby wall, so you'd be bludgeoned to death before you had time to asphyxiate...



Methinks thou dost confuseth velocity with acceleration

ETA: OTOH, you can always define a frame of reference in which you're moving at speeds close to Tau-zero. But so would the rest of the solar system, so big deal :P
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Re: What-if 0064: "Rising Steadily"

Postby rmsgrey » Tue Sep 24, 2013 4:51 pm UTC

cellocgw wrote:
rmsgrey wrote:I think not enough attention has been given to the question of what "up" means here - if your only motion relative to the ground is a steady 1 foot per second directly away from the Earth's centre of gravity (a forced geosynchronous orbit with steadily increasing radius) then you'd exceed the speed of light before leaving the solar system (if you started on the equator, then you'd hit light speed somewhere between Uranus and Neptune's orbits). Other simple movement schemes would tend to do things like have you (try to) pass through a nearby wall, so you'd be bludgeoned to death before you had time to asphyxiate...



Methinks thou dost confuseth velocity with acceleration

ETA: OTOH, you can always define a frame of reference in which you're moving at speeds close to Tau-zero. But so would the rest of the solar system, so big deal :P


A circle with a radius of 4 light hours would have a circumference of over 24 light hours, or over one light day, so in order to travel the circumference in one day, you'd have to be moving faster than the speed of light...

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Re: What-if 0064: "Rising Steadily"

Postby davidstarlingm » Tue Sep 24, 2013 5:24 pm UTC

rmsgrey wrote:I think not enough attention has been given to the question of what "up" means here - if your only motion relative to the ground is a steady 1 foot per second directly away from the Earth's centre of gravity (a forced geosynchronous orbit with steadily increasing radius) then you'd exceed the speed of light before leaving the solar system (if you started on the equator, then you'd hit light speed somewhere between Uranus and Neptune's orbits). Other simple movement schemes would tend to do things like have you (try to) pass through a nearby wall, so you'd be bludgeoned to death before you had time to asphyxiate...

Hmm, very good point. That 1000 mph of tangential velocity has got to go somewhere. I suppose you could lose tangential velocity slowly as you ascended? Or perhaps the 1000 mph is maintained but not increased?

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Re: What-if 0064: "Rising Steadily"

Postby cellocgw » Tue Sep 24, 2013 5:49 pm UTC

rmsgrey wrote:
cellocgw wrote:
rmsgrey wrote:I think not enough attention has been given to the question of what "up" means here - if your only motion relative to the ground is a steady 1 foot per second directly away from the Earth's centre of gravity (a forced geosynchronous orbit with steadily increasing radius) then you'd exceed the speed of light before leaving the solar system (if you started on the equator, then you'd hit light speed somewhere between Uranus and Neptune's orbits). Other simple movement schemes would tend to do things like have you (try to) pass through a nearby wall, so you'd be bludgeoned to death before you had time to asphyxiate...



Methinks thou dost confuseth velocity with acceleration

ETA: OTOH, you can always define a frame of reference in which you're moving at speeds close to Tau-zero. But so would the rest of the solar system, so big deal :P


A circle with a radius of 4 light hours would have a circumference of over 24 light hours, or over one light day, so in order to travel the circumference in one day, you'd have to be moving faster than the speed of light...


I'm still not getting what you're claiming. The person is not trying to complete a circumference, nor is he/she trying to remain over the same spot on the Earth's surface. As I suggested in a previous post, Coriolus takes place. However you posit the motion happening, the distance between the person and the Earth's center increases at 1 ft/sec. If you're in the plane of the ecliptic, this might require some yo-yo action from summer to winter, I guess, but there's no requirement that the person remain vertically over the starting point on the surface.
Alternatively, if you take off perpendicular to the ecliptic, a little travel to the cross-product vector thru the Sun will let you maintain a "conical" distance from the Earth very smoothly!
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Re: What-if 0064: "Rising Steadily"

Postby PsiSquared » Tue Sep 24, 2013 7:06 pm UTC

DanD wrote:
Eutychus wrote:I'm puzzled about the 2km up. There are places on earth that are 2km up where it certainly isn't freezing, like Quito.


At or near the equator, the (climatic) snow line seems to be around 4-5km, and then falling once you get past the tropics. So Randal might be basing this on a more northerly latitude. Or, and I don't really have much to back this up, solar heating of the ground and possibly anabatic winds might combine to warm the atmosphere near the earth even at altitude in a way that doesn't happen in free air.


Randall is probably basing his scenario on the International Standard Atmosphere model (or something similar). The ground temperature in this model is 15 C (the global average) and it goes down by 6.5 C for every kilometer of altitude, which translates to 7.13 C per hour.

So, according to this model, you'll reach the freezing point of water at 2 hours 6 minutes, which is right on the nose. You'll also reach 0 F (-17.8 C) at 4 hours 36, which is a bit off, but still pretty close to Randall's estimate of 4 hours.

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Re: What-if 0064: "Rising Steadily"

Postby davidstarlingm » Tue Sep 24, 2013 7:29 pm UTC

cellocgw wrote:The person is not trying to complete a circumference, nor is he/she trying to remain over the same spot on the Earth's surface.

Well, the OP doesn't say the person ever moves tangentially relative to the point of departure, other than the vertical change in distance. If you think the person's position does change relative to that spot on the Earth's surface, when does it begin doing so?

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Re: What-if 0064: "Rising Steadily"

Postby eran_rathan » Tue Sep 24, 2013 8:18 pm UTC

davidstarlingm wrote:
cellocgw wrote:The person is not trying to complete a circumference, nor is he/she trying to remain over the same spot on the Earth's surface.

Well, the OP doesn't say the person ever moves tangentially relative to the point of departure, other than the vertical change in distance. If you think the person's position does change relative to that spot on the Earth's surface, when does it begin doing so?


That begs an interesting question about the angular momentum of the system of {Earth & Megan} - how much does she slow the rotation of the Earth when she leaves the heliopause (assuming conservation of angular momentum)?
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Re: What-if 0064: "Rising Steadily"

Postby Pfhorrest » Tue Sep 24, 2013 8:44 pm UTC

I think the assumption in the scenario is that she is effectively sitting on a rocket which is kept pointed at the center of the Earth, applying exactly as much thrust as necessary to move her at the 1ft/sec velocity relative to the Earth, and without all the side effects of actually sitting on a rocket (what with the exhaust and the burning and the loud noises waugh glaven). So, how does she move relative to the point on the surface of the Earth she started at? The same way a rocket shooting straight up would: once she gets far enough up, the Earth seems to be rotating away beneath her because she doesn't have enough tangental velocity to stay geosynchronous at her new height.

If she wanted to stay geosynchronous, she would have to also accelerate sideways (i.e. perpendicular to "up") to keep at it, and even with this magic infinite-fuel intangible rocket that's moving her, she's going to hit a hard limit to that endeavor at around 12/π ≈ 3.8 light-hours "up" (i.e. somewhere a bit shy of the orbit of Neptune).
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Re: What-if 0064: "Rising Steadily"

Postby davidstarlingm » Tue Sep 24, 2013 8:59 pm UTC

Pfhorrest wrote:I think the assumption in the scenario is that she is effectively sitting on a rocket which is kept pointed at the center of the Earth, applying exactly as much thrust as necessary to move her at the 1ft/sec velocity relative to the Earth, and without all the side effects of actually sitting on a rocket (what with the exhaust and the burning and the loud noises waugh glaven). So, how does she move relative to the point on the surface of the Earth she started at? The same way a rocket shooting straight up would: once she gets far enough up, the Earth seems to be rotating away beneath her because she doesn't have enough tangental velocity to stay geosynchronous at her new height.

So she'll have a 1000 mph sideways velocity added on for the duration of the trip? That's going to get her ejected from the solar system long before the 1 ft/sec specified.

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Re: What-if 0064: "Rising Steadily"

Postby Pfhorrest » Tue Sep 24, 2013 9:09 pm UTC

davidstarlingm wrote:
Pfhorrest wrote:I think the assumption in the scenario is that she is effectively sitting on a rocket which is kept pointed at the center of the Earth, applying exactly as much thrust as necessary to move her at the 1ft/sec velocity relative to the Earth, and without all the side effects of actually sitting on a rocket (what with the exhaust and the burning and the loud noises waugh glaven). So, how does she move relative to the point on the surface of the Earth she started at? The same way a rocket shooting straight up would: once she gets far enough up, the Earth seems to be rotating away beneath her because she doesn't have enough tangental velocity to stay geosynchronous at her new height.

So she'll have a 1000 mph sideways velocity added on for the duration of the trip? That's going to get her ejected from the solar system long before the 1 ft/sec specified.

I was actually going to mention in that last post that past geosynchronous orbit the magic intangible rocket thrusters would need to push her toward the Earth to keep her distance from the center of the Earth increasing by only 1ft/sec, but then I thought that would be redundant with the "applying exactly as much thrust as necessary to move her at the 1ft/sec" already specified. (Though I guess if the business end of the intangible rocket is pointed toward the Earth as specified, that thrust would have to have a negative magnitude, so maybe it's not so redundant after all). That part also solves your concern.
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Re: What-if 0064: "Rising Steadily"

Postby gmalivuk » Tue Sep 24, 2013 9:56 pm UTC

Orbital velocity doesn't fall below 1000mph until you're well past the Moon.
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Re: What-if 0064: "Rising Steadily"

Postby rmsgrey » Tue Sep 24, 2013 10:28 pm UTC

An alternate interpretation of "rising steadily" is that, rather than recede from Earth at 1 foot per second, you travel in the direction that maximises your rate of increase of gravitational potential (usually directly opposite the direction that would maximise your rate of decrease of gravitational potential) at such a speed that, after 1 second, your distance from the equipotential surface you are on along the path you take will be exactly one foot.

Of course, that would do weird things to your path relative to the ground, but at least you stay within the cosmic speed limit...

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Re: What-if 0064: "Rising Steadily"

Postby rmsgrey » Tue Sep 24, 2013 10:36 pm UTC

cellocgw wrote:
rmsgrey wrote:
cellocgw wrote:
rmsgrey wrote:I think not enough attention has been given to the question of what "up" means here - if your only motion relative to the ground is a steady 1 foot per second directly away from the Earth's centre of gravity (a forced geosynchronous orbit with steadily increasing radius) then you'd exceed the speed of light before leaving the solar system (if you started on the equator, then you'd hit light speed somewhere between Uranus and Neptune's orbits). Other simple movement schemes would tend to do things like have you (try to) pass through a nearby wall, so you'd be bludgeoned to death before you had time to asphyxiate...



Methinks thou dost confuseth velocity with acceleration

ETA: OTOH, you can always define a frame of reference in which you're moving at speeds close to Tau-zero. But so would the rest of the solar system, so big deal :P


A circle with a radius of 4 light hours would have a circumference of over 24 light hours, or over one light day, so in order to travel the circumference in one day, you'd have to be moving faster than the speed of light...


I'm still not getting what you're claiming. The person is not trying to complete a circumference, nor is he/she trying to remain over the same spot on the Earth's surface. As I suggested in a previous post, Coriolus takes place. However you posit the motion happening, the distance between the person and the Earth's center increases at 1 ft/sec. If you're in the plane of the ecliptic, this might require some yo-yo action from summer to winter, I guess, but there's no requirement that the person remain vertically over the starting point on the surface.
Alternatively, if you take off perpendicular to the ecliptic, a little travel to the cross-product vector thru the Sun will let you maintain a "conical" distance from the Earth very smoothly!

The Earth rotates - if you're directly above one spot on the ground at midnight UTC, then to be directly above that spot on the ground at noon UTC, you need to be out in the opposite direction relative to the fixed stars (the further from the equator you are, the shorter the actual distance you need to travel each day)

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Re: What-if 0064: "Rising Steadily"

Postby ShuRugal » Tue Sep 24, 2013 11:44 pm UTC

FrobozzWizard wrote:River Tam has let me down with her calm assurance that we'd freeze to death before asphyxiating!



Well, that depends. Rising through atmosphere, you won't be exposed to enough cold fast enough to freeze before your oxygen runs out. Dumped into deep space you would shed heat much more rapidly. Of course, i'd be more worried about the other effects of being exposed to a vacuum.

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Re: What-if 0064: "Rising Steadily"

Postby gmalivuk » Tue Sep 24, 2013 11:58 pm UTC

Would you, though? I imagine you'd radiate heat away more slowly than it gets carried away by air.
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Re: What-if 0064: "Rising Steadily"

Postby rmsgrey » Wed Sep 25, 2013 12:07 am UTC

gmalivuk wrote:Would you, though? I imagine you'd radiate heat away more slowly than it gets carried away by air.


If you're close enough to a radiant heat source, shedding heat becomes a serious challenge...

Radiative heat loss is much higher in deep space (or in a shadow) but, yeah, my first instinct is that the vacuum preventing conduction/convection is going to be a bigger effect than the increase in net radiation.

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Re: What-if 0064: "Rising Steadily"

Postby davidstarlingm » Wed Sep 25, 2013 12:16 am UTC

Radiative cooling will take several hours at minimum before your temperature will drop more than a degree or two, IIRC.

codertao
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Re: What-if 0064: "Rising Steadily"

Postby codertao » Wed Sep 25, 2013 12:57 am UTC

Wanted to point out as an almost pilot:

If subject isn't tethered to the lat/lon coordinates (can move tangentially), she will be pushed by the wind, and generally move with the air mass. Wind chill effect should be negligible. At least for the first few kilometers.

Winds aloft of 40 knots are only relevant because of what they do to travel times / where you are relative to the ground.

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Re: What-if 0064: "Rising Steadily"

Postby rmsgrey » Wed Sep 25, 2013 1:04 am UTC

davidstarlingm wrote:Radiative cooling will take several hours at minimum before your temperature will drop more than a degree or two, IIRC.


Using the calculator on this site, a naked human with 2 square meters of skin radiating as a black-body at a temperature of 34 Celsius against a background of 3K radiates at around 1kW - so, treating the human body as mostly water, with a specific heat capacity of around 4 kJ/K/kg, and a typical body mass of around 60kg, it would take about 4 minutes to lose enough heat energy to reduce the average body temperature by 1K - call it 5 minutes to account for rounding errors.

Of course, that's ignoring the body's natural heat production - spot research turns up a basal metabolic rate of 90W, which can be supplemented by additional heat generation, but on its own is enough to make it "about 5 minutes" rather than "less than 5 minutes". To get it up to an hour, you'd need to be producing over 90% of the heat being radiated (call it 900W or ten times the basic rate).

Of course, the other factor is the body's ability to conserve core heat at the expense of extremities, which I'm not even going to guess at.

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Re: What-if 0064: "Rising Steadily"

Postby gmalivuk » Wed Sep 25, 2013 1:51 am UTC

Well, since 1K isn't enough to freeze to death, but 5 minutes is enough to asphyxiate, I doubt too much additional precision would really be that useful.
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Re: What-if 0064: "Rising Steadily"

Postby duckysherwood » Wed Sep 25, 2013 4:12 am UTC

There is one person who rose to almost 10,000m without oxygen, without adequate clothing, and lived. DO NOT TRY THIS AT HOME.

Her name is Ewa Wisnierska; she's a paraglider who got sucked into a thunderstorm.

There is a great five-part series on YouTube about it: search for her name.

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Durandal_1707
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Re: What-if 0064: "Rising Steadily"

Postby Durandal_1707 » Wed Sep 25, 2013 8:24 am UTC

Wait, if the Death Zone is above "all but the highest mountains", then that means the very highest mountains go into it.

So how do people manage to climb Everest and not die of asphyxiation?

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Re: What-if 0064: "Rising Steadily"

Postby Pfhorrest » Wed Sep 25, 2013 8:27 am UTC

Very carefully.

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