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Everything posted by Mr Skeptic
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What if I could digest cellulose?
Mr Skeptic replied to Genecks's topic in Biochemistry and Molecular Biology
To my knowledge, no animals can digest cellulose themselves and rely on microbes to do that for them. Typically, they have some sort of "fermentation vat" in their digestive system for this to happen. If humans were able to digest cellulose, that would probably be very bad. We currently don't eat much cellulose and fiber helps clean out our digestive system. Now if we had an animal that could digest cellulose directly, that could be very useful. As it is, the bacterial "middleman" takes a good bit of the energy, and also in some species produces methane, which is another energy loss and a greenhouse gas. -
No one ever said that standing up for your rights is the safe nor polite thing to do.
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Oh, I think I see. When the fan starts blowing, it produces lift at that point. So you have to subtract the lift from the fan from the center of mass (treat it as a negative mass).
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Technologically/Intellectually Superior Aliens: "Unpleasant Visits"?
Mr Skeptic replied to tristan's topic in Speculations
Indeed. Probably used by humans as tools or discarded in trash heaps. I wonder if we've found any dragon bones. Well I was kind of joking, considering dinosaur bones and all. But you do have a point. Where's the stuffed dragons, or other trophies from such an impressive kill? You'd think someone would have kept a tooth or a claw at least. Merged post follows: Consecutive posts merged Or such as intelligence. Merged post follows: Consecutive posts merged Glass was known about in 3500 BC in Mesopotamia, and by the Romans at around the time of Jesus (depicted elsewhere in that painting). Regardless, clear materials also reflect light, and there is no bright spots on the clear area where there might be some transparent material. -
Is cheating on single player computer games wrong? Do you consider the following cheating?: 1) Using the game's built in cheat codes? 2) Purposely using a bug in the game to benefit your player? 3) Saving/Loading to avoid losses? 4) Looking at online walkthroughs?
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How to calculate the pressure ratio of a fan ?
Mr Skeptic replied to kemo1988's topic in Engineering
The name, model number, manufacturer, that sort of thing. Merged post follows: Consecutive posts mergedAlso, you might consider using a fan that produces more pressure but less airflow; such a fan will have less surface area. Think about it: how big a hole do you want on the upper surface of your craft? If you have an inflatable skirt at the bottom of your craft, this will give you a wide margin of airflow you can use (excess airflow lifts the skirt and allows more air to leave, too little airflow lowers the skirt and provides a tighter seal. For example, if the skirt is 1 mm off the ground and your craft has a circumference of 8 m, then the surface area under the craft will be about 60 times less than that of your 0.5 m^2 fan. -
That is, of course, the problem with open polls. If the answers have potential to be embarrassing, then having the poll open vs closed could affect the results significantly. On a closed poll people can say what they voted for if they wish to. In any case, said descriptions (like Paranoia's) are going to be far more accurate than the answer to a multiple choice question. Merged post follows: Consecutive posts mergedMy own current strategy is "a penny saved is a penny I don't need to earn"
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Solving the zombie problem:
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Maybe it is equivalent to rejecting the Principle of Non-Contradiction.
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Done. I also changed the poll to private, since I don't think people want to go telling everyone how much they earn. Is that OK?
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And they can and do abuse said "respect" for the law, by doing such things as implicitly getting your permission to search without a warrant ("I'm going to search your car now, is that OK?" rather than "May I search your car"). People should feel free to disrespect the police, and the police had better not abuse their government-granted powers to limit your free-speech ability to disrespect them. Being provocative is not a crime, nor should a cop pay special attention to see if you do anything wrong and then nail you for it, just because you said something disrespectful to him.
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Technologically/Intellectually Superior Aliens: "Unpleasant Visits"?
Mr Skeptic replied to tristan's topic in Speculations
These are pretty good evidence against trusting the factual accuracy of alien UFO claims. 1) It looks like your typical "lights in the sky" meteorite. 2) As a craft, this cannot be how it actually looks -- the person inside should not be visible, or if it is actually intended to be an "open" ship, these people have no idea how nasty wind can be at supersonic speeds. -
How to calculate the pressure ratio of a fan ?
Mr Skeptic replied to kemo1988's topic in Engineering
Oh, I messed something up. The area I calculated is 4 times too big, because I used diameter as radius. After recalculating correcting for that, I get 0.012 bar, so just over what you need. If you can give the info on the fan, I might be able to look up the actual numbers. -
I trust that the Democrats are far too honorable to use a disaster like this oil spill for political gain, like the Republicans did with the 9/11 attacks.
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Is Hawking getting old or what?
Mr Skeptic replied to Realitycheck's topic in Modern and Theoretical Physics
Caution regarding aliens is indeed very wise. Think about it: consider the sort of technology needed to receive and understand radio signals of absurdly small amplitude, and the rate at which technology develops. It's almost guaranteed that any civilizations that detect us could be a good million years more technologically advanced than we are. And what happens when a more advanced civilization meets a less advanced civilization? Ask the Native Americans, or the Africans. But maybe the technology will make this problem moot. -
Would killing the rich solve economics issues in times of crisis?
Mr Skeptic replied to Genecks's topic in Politics
You're forgetting that the merchant also profits. The increase in profits of the apple farmer between my first and second examples came entirely 100% out of the profits of the merchant, with no change for the corn farmer. My claim is that at least one of the two examples is an unfair distribution. I am not claiming any of the examples is a fair distribution -- they could all be unfair. The point is that at least one of the examples is unfair, and yet all are voluntary and beneficial for all regardless. And relating it back to the subject of the thread, whoever is the one that gets the disproportionate portion of the profits, is getting rich at the expense of the others (even while all benefit and participate voluntarily). -
Because in SI units people never use a measure of mass as a measure of force. How many kilograms do you weigh?
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It's Not What Politicians Say but What We Hear
Mr Skeptic replied to Syntho-sis's topic in Science News
About twice as much for the opposing candidate, in case anyone was wondering. Which is pretty significant. Original study: http://www.psychsystems.net/lab/06_Westen_fmri.pdf -
By the way, how much area is there below your craft, and how much does your craft weigh?
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Well, there's that and then there's this guy: http://www.oregonlive.com/clackamascounty/index.ssf/2010/02/clackamas_man_exercises_free_s.html Always nice to see someone standing up for our rights.
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Would killing the rich solve economics issues in times of crisis?
Mr Skeptic replied to Genecks's topic in Politics
Right, but in the post Pangloss had replied to, I had separated wealth creation, value creation, and distribution. Distribution was the only part that I claimed was zero sum. So for example, if the farmers value the product they produce at 1 dollar and the product the other produces at 2 dollars, and the merchant values them all at 2 dollars, then so long as the merchant purchases the products and the farmers end up with none of their own product, there is no particular distribution that optimizes value. Anyhow, even if the thing is not exactly zero sum, my point is that there is a range of possible distributions that satisfy the "voluntary action" requirement for voluntary trading, and that an increase in someone's share of distribution is going to cost some else. -
Technologically/Intellectually Superior Aliens: "Unpleasant Visits"?
Mr Skeptic replied to tristan's topic in Speculations
You'd think that if there actually were any oversized reptiles, there'd be some evidence -- bones, perhaps. -
How to calculate the pressure ratio of a fan ?
Mr Skeptic replied to kemo1988's topic in Engineering
Well let's see: (don't trust me, I've never done anything remotely similar to this before) Power = 13 HP = 9,694 watts (that's pretty impressive for a fan!) If 100% efficiency, Power --> kinetic energy/s ==> 9,694 W = 9,694 J/s KE/s = (1/2) M v^2/s = 9,694 J/s ==> v = sqrt(9,694 J * 2 / M) where v is air velocity Flow Rate = M / s = density * volume / s = density * area * v Density (air, 25 C) = 1.184 kg/m^3 Area = pi * r^2 = pi * (0.8 m)^2 = 2 m^2 Flow Rate = density * area * v = 2.38 kg/m * v = 2.38 kg/m * sqrt(9,694 J * 2 / M) = 331.39 kg/s * sqrt(kg/M) = M/s ==> (M/kg)^(3/2) = 331.39 ==> M/kg) = 331.39^(2/3) = 47.89 ==> M = 47.89 kg So Flow rate = 47.89 kg/s, v = sqrt(9,694 J * 2 / M) = 20.12 m/s P = F/A = (M * v / s)/A = 47.89 kg * 20.12 m/s / s / 2 m^2 = 482 pascals = 0.0048 bar So half of what you need if my half-guesswork calculations are right. The last bit in particular seems dubious, since the air would come to a stop and I'd need different numbers. So, how close was I? Hand over the model number and company name, etc. -
Would killing the rich solve economics issues in times of crisis?
Mr Skeptic replied to Genecks's topic in Politics
I very specifically said that the farmer profited from the trade, as did everyone else involved. What I said is that any increase in profits by one party comes at the expense of a decrease in profits of another. "Harmed" in that sense, as compared to a previous example. Can the apple farmer increase his profits without reducing the profits of the corn farmer and/or the merchant? Can the merchant? -
Technologically/Intellectually Superior Aliens: "Unpleasant Visits"?
Mr Skeptic replied to tristan's topic in Speculations
Well there are some fairly universal things. Mankind has always wanted to fly. There have always been UFO's (obviously). Mankind has always believed in entities more powerful than men. It's not much of a stretch to go to flying, powerful, supernatural humanoids. And they don't even need to exist for that.