What-if 0066: "500 MPH"

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Re: What-if 0066: "500 MPH"

Postby eran_rathan » Thu Oct 10, 2013 11:57 am UTC

Philbert wrote:Does NASA actually print the name on each asteroid?

Not yet. Their laser isn't that big, and do you know how hard it is to hit something that small and that far away?


(yes, being silly. And I don't know, but I think there is a great big list run by the IAU that does have the names of everything we've decided to name in space. check out http://iau.org/public/themes/naming/ for more info.)

Edit to Add: list of all minor planets: http://www.minorplanetcenter.net/iau/lists/MPNames.html
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Re: What-if 0066: "500 MPH"

Postby Red Hal » Thu Oct 10, 2013 2:38 pm UTC

Philbert wrote:Does NASA actually print the name on each asteroid?
Don't be silly. They send out a probe with a banner made of ultralight material which they unfurl.
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Re: What-if 0066: "500 MPH"

Postby Jackpot777 » Thu Oct 10, 2013 3:19 pm UTC

PM 2Ring wrote:
Diadem wrote:
PM 2Ring wrote:
Diadem wrote:"500 mph in normal units" doesn't work
"500 mph in civilized units" doesn't work either.

But
500 mph in km/h
does work. So does
500 mph
but it gives the answer in m/s. And neither of my searches work if you quote them. I suspect that quotes cause the search engine to bypass the calculator.

I was joking, of course.

Understood. I also tried "500 mph in sane units" (without the quotes). :)

Diadem wrote:But on a serious note. Being able to ask "X in metric" (and yes, without the quotation marks, of course) would be useful, because it's not always obvious quantity an unknown unit is even referring to. Likewise I suppose "X in imperial" would be useful to have for Americans. It's a shame google doesn't support that.

Agreed, although we really need three terms, since several American units are not equal to the Imperial units formerly used in British Commonwealth countries, notably several of the units of volume (especially the gallon), as well as the ton.


Whenever anyone tells me the imperial measurements are more "natural", I go to liquid measurements.

A fluid ounce, yes? In Britain, a fl.oz is 28.4ml ...in America, it's 29.6ml. So an American pint is going to be slightly bigger than a UK one, right? Nope. American pints are 16 fl.oz but a British one is 20 fl.oz, so the British pint is just over 1.2 American pints. So a US gallon is around 1.2 UK gallons (3.79 litres compared to 4.55 litres to be exact).

An American 2014 Subaru Forester that gets 32mpg on the highway ...ship it to Britain, it's getting 38.4mpg. That's not "natural".
Last edited by Jackpot777 on Thu Oct 10, 2013 3:21 pm UTC, edited 1 time in total.

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Re: What-if 0066: "500 MPH"

Postby Jackpot777 » Thu Oct 10, 2013 3:20 pm UTC

Red Hal wrote:
Philbert wrote:Does NASA actually print the name on each asteroid?
Don't be silly. They send out a probe with a banner made of ultralight material which they unfurl.


Image

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Re: What-if 0066: "500 MPH"

Postby gmalivuk » Thu Oct 10, 2013 6:45 pm UTC

Jackpot777 wrote:
PM 2Ring wrote:
Diadem wrote:
PM 2Ring wrote:
Diadem wrote:"500 mph in normal units" doesn't work
"500 mph in civilized units" doesn't work either.

But
500 mph in km/h
does work. So does
500 mph
but it gives the answer in m/s. And neither of my searches work if you quote them. I suspect that quotes cause the search engine to bypass the calculator.

I was joking, of course.

Understood. I also tried "500 mph in sane units" (without the quotes). :)

Diadem wrote:But on a serious note. Being able to ask "X in metric" (and yes, without the quotation marks, of course) would be useful, because it's not always obvious quantity an unknown unit is even referring to. Likewise I suppose "X in imperial" would be useful to have for Americans. It's a shame google doesn't support that.

Agreed, although we really need three terms, since several American units are not equal to the Imperial units formerly used in British Commonwealth countries, notably several of the units of volume (especially the gallon), as well as the ton.


Whenever anyone tells me the imperial measurements are more "natural", I go to liquid measurements.

A fluid ounce, yes? In Britain, a fl.oz is 28.4ml ...in America, it's 29.6ml. So an American pint is going to be slightly bigger than a UK one, right? Nope. American pints are 16 fl.oz but a British one is 20 fl.oz, so the British pint is just over 1.2 American pints. So a US gallon is around 1.2 UK gallons (3.79 litres compared to 4.55 litres to be exact).

An American 2014 Subaru Forester that gets 32mpg on the highway ...ship it to Britain, it's getting 38.4mpg. That's not "natural".
Some of your math is backward. There are 1.2 US gallons in a UK one, and so your apparent fuel efficiency goes down in Britain, not up.

You probably would have caught this if your brain hadn't turned to mush from playing the measurement game on easy mode.
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Re: What-if 0066: "500 MPH"

Postby oneeyedziggy » Fri Oct 11, 2013 7:31 pm UTC

Eternal Density wrote:What if the Syfy channel got hold of this image?
Direct to TV Movie: HYPERDINADO. Enough Said!


this image made me wonder "Under ANY circumstances, could an 'intact' dinosaur have been ejected into space and still be out there in earth trailing orbit or beyond?", because that'd be about the coolest thing short of intelligent aliens to find while exploring space... a perfectly preserved dinosaur! I know the hypercane wouldn't do it given the much higher that 500 mph value of escape velocity, it'd be much more likely to have been the product of a comet or meteor strike, but even then the dino would likely have been vaporized, or at best fallen back to a molten earth/moon (though finding a lava-encased dino on the moon would still be pretty cool)

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Re: What-if 0066: "500 MPH"

Postby ahecht » Sat Oct 12, 2013 5:02 pm UTC

What Randall didn't mention here is that the wind speed needed to pick up an object is the same as that object's terminal velocity (and yes, if you look it up, the terminal velocity of a human is right about 120 mph). It makes sense if you think about it -- terminal velocity is the speed at which your net acceleration is 0, which means that your weight (in units of force) is equal to the force exerted by the air rushing past you. If instead of the air being still and you moving, you switch it to the other way around, air blowing at your terminal velocity has enough force to counteract the force holding you on the ground.

This is why knowing the terminal velocity of various animals and objects is useful to hurricane/tornado/dust devil researchers, and why I know that the terminal velocity of a kangaroo rat is 12 m/s.

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Re: What-if 0066: "500 MPH"

Postby svenman » Sat Oct 12, 2013 10:39 pm UTC

gmalivuk wrote:One thing I love about this one is that he seems to have graded his language quite a bit, in response to the fact that the asker is only 7 years old.

Indeed. I suppose the mustard extraneous word in the penultimate (or, if you prefer, last-but-one) sentence is the result of an oversight when editing down a previous version which could have been something like:
Instead, what you really should worry about is the thing that created the 500 mph winds.
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Re: What-if 0066: "500 MPH"

Postby Quizatzhaderac » Tue Oct 15, 2013 1:22 pm UTC

airdrik wrote:why not figure out to make [a hypercane] on ... one of the moons that has an atmosphere?
Because they have no atmosphere to form a hyper cane with. Though I do agree with you not-in-my-backyard attitude. Maybe Titan would be good? uninhabited, thick atmosphere, definitive surface, cool enough not to melt our instruments.
ahecht wrote:...why I know that the terminal velocity of a kangaroo rat is 12 m/s.
Bravo, I award you 17.2 internets for that.
what-if wrote:...the force from a 500 mph wind is several times stronger than the force from a 300 mph wind.
What's the relationship of speed to force? I would have guessed F= kv or F = kv2.
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Re: What-if 0066: "500 MPH"

Postby Mikeski » Tue Oct 15, 2013 3:53 pm UTC

Quizatzhaderac wrote:What's the relationship of speed to force? I would have guessed F= kv or F = kv2.

Fluid dynamics is covered by multiple classes in a mechanical engineering program at a university. There's a million-dollar prize associated with proving the century-old Navier-Stokes equations always have a solution.

At a very high level (consider-a-spherical-cow-in-a-vacuum high-level), force is proportional to v2. At the speeds we're talking about, anyway... though we're closing in on Mach 1 (768 mph), where, as an electrical engineer, I just say "yeah, you should ask someone else."

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Re: What-if 0066: "500 MPH"

Postby Quizatzhaderac » Tue Oct 15, 2013 4:32 pm UTC

Yes-yes, I'm sure is all very complicated once everythings taken into account. But if Randal can know "the force from a 500 mph wind is several times stronger than the force from a 300 mph wind.", and he's using actual math for that statement, he would have needed to use some specific formula. Given his outcome, it must scale faster than v2.
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Re: What-if 0066: "500 MPH"

Postby rmsgrey » Tue Oct 15, 2013 4:44 pm UTC

Quizatzhaderac wrote:
airdrik wrote:[...]moons that has an atmosphere?
Because they have no atmosphere[...]


Something seems to have gone wrong here...

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Re: What-if 0066: "500 MPH"

Postby gmalivuk » Tue Oct 15, 2013 7:24 pm UTC

Quizatzhaderac wrote:Yes-yes, I'm sure is all very complicated once everythings taken into account. But if Randal can know "the force from a 500 mph wind is several times stronger than the force from a 300 mph wind.", and he's using actual math for that statement, he would have needed to use some specific formula. Given his outcome, it must scale faster than v2.
500^2/300^2 = 2.77, and I see nothing wrong with using the nonspecific word "several" to mean "about three".
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Re: What-if 0066: "500 MPH"

Postby Mikeski » Tue Oct 15, 2013 7:30 pm UTC

Quizatzhaderac wrote:he's using actual math for that statement, he would have needed to use some specific formula.

The second does not follow from the first the way you think it does. The right answer for stuff like this probably involves the Navier-Stokes equations, which are differential equations. So yes, he may have some Wolfram-Alpha/Mathematica solution, but he didn't work this out on paper using algebra.

Or if he did, he used a simplified form like the drag equation, which is what I did above when I said v2 was close enough for government work. And he abstracted 1.62=2.8 to "several times".

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Re: What-if 0066: "500 MPH"

Postby airdrik » Thu Oct 24, 2013 4:19 pm UTC

gmalivuk wrote:
Quizatzhaderac wrote:Yes-yes, I'm sure is all very complicated once everythings taken into account. But if Randal can know "the force from a 500 mph wind is several times stronger than the force from a 300 mph wind.", and he's using actual math for that statement, he would have needed to use some specific formula. Given his outcome, it must scale faster than v2.
500^2/300^2 = 2.77, and I see nothing wrong with using the nonspecific word "several" to mean "about three".

And he must have used "several times" because it sounds a lot bigger and more impressive than "a couple times" which is far more accurate :twisted:

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Re: What-if 0066: "500 MPH"

Postby davidstarlingm » Thu Oct 24, 2013 4:24 pm UTC

airdrik wrote:
gmalivuk wrote:500^2/300^2 = 2.77, and I see nothing wrong with using the nonspecific word "several" to mean "about three".

And he must have used "several times" because it sounds a lot bigger and more impressive than "a couple times" which is far more accurate :twisted:

In common parlace, "a couple" means 2 and "several" means 3 or more. 2.77 is closer to 3 than it is to 2.

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Re: What-if 0066: "500 MPH"

Postby airdrik » Thu Oct 24, 2013 5:19 pm UTC

davidstarlingm wrote:
airdrik wrote:
gmalivuk wrote:500^2/300^2 = 2.77, and I see nothing wrong with using the nonspecific word "several" to mean "about three".

And he must have used "several times" because it sounds a lot bigger and more impressive than "a couple times" which is far more accurate :twisted:

In common parlance, "a couple" means 2 and "several" means 3 or more. 2.77 is closer to 3 than it is to 2.

Did you hear that? It sounded something like a wooshing sound.
Apparently the sarcasm in the "far more accurate :twisted:" wasn't apparent enough

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Re: What-if 0066: "500 MPH"

Postby davidstarlingm » Thu Oct 24, 2013 6:36 pm UTC

airdrik wrote:Did you hear that? It sounded something like a wooshing sound.
Apparently the sarcasm in the "far more accurate :twisted:" wasn't apparent enough

AAAAND missed it.

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Re: What-if 0066: "500 MPH"

Postby gmalivuk » Thu Oct 24, 2013 7:08 pm UTC

A couple is about 2. A few is between three and some, which itself is between none and most. Several is usually more than some and less than many, but could also be as little as a few. It is approximately equal to a number but generally less than quite a few.

I can't understand why this is so difficult for people to understand.
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Re: What-if 0066: "500 MPH"

Postby speising » Thu Oct 24, 2013 7:19 pm UTC

only for some.

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Re: What-if 0066: "500 MPH"

Postby svenman » Sat Oct 26, 2013 9:43 pm UTC

Oh, quite a few, I can assure you!
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Re: What-if 0066: "500 MPH"

Postby Quizatzhaderac » Mon Oct 28, 2013 5:50 pm UTC

Okay, I was under the impression that several was a couple of few. (actually four or more; I blame my middle school English teacher)
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