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SH3RL0CK

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Posts posted by SH3RL0CK

  1. Or you could just get a full plug-in electric Tesla:

    3388564188_4427beac12.jpg

     

    - 0-60 mph in 5.6 seconds

    - 120 mph top speed

    - Seating for 5 adults + 2 child seats

    - Up to 300 mile range

    - 45 minute QuickCharge

    - Charges from 120V, 240V or 480V

    - 5 minute battery swap

     

    Yes, this is a good start. I'd consider it for to and from work; but I'm not completely sold.

     

    It isn't uncommon to need to haul more than 5 people (many couples have more than three kids). "Seating" for 5 people; but only two car seats (required by law) really means I can only carry four people if I have children. If I had three children (not uncommon), I should not buy this vehicle.

     

    Three hundred miles is good to and from work; but I occasionally need to go further than that...and "up to" concerns me if I need to go, say, 250 miles in the rain. A quick charge and battery swap is good; but the places that have these aren't readily available on the road. If I use it to drive a lot (perhaps I use it to travel for work) I should not buy this vehicle.

     

    What if I need to carry a large amount of "stuff" with me? This car isn't as capable as an SUV. If I will, even occasionally, need to haul "stuff" I should not buy this vehicle.

     

    Most importantly, the cost of $50k is very high; I can buy a different vechicle for $25k; leaving me $25k to buy the extra gas. At a conservative $5 per gallon, this can buy 5k gallons; at a conservative 20 mpg milage this is equivalent to an 100,000 miles of travel. This car could even cost me more than buying a gas-guzzelling SUV (let alone an efficient Prius) and it has much less capability than a SUV.

  2. hiw big do you think these turbine are they are only small so that they dont desturb anything for ages

    also i was talking about the turbines in the water being cheaper then dams not fossil feuls

    only an idiot would think they are cheap with the comsupmtion rate they will most definatly run or sooner rather then later

    this teard was onrianly called globel warming in the genetics area so i was thinking about the enviroment when i posted this

    whats better to save the ecomimy that can sort it self out or the enviroment that has to have lots of help being sorted out because unless a imagenery fairy pixie thing will save who will. we the adluts have to be resonceible for making sure children inherit a clean safe beautiful world not some stink hole full of pollution

    plus i am responding your your points i just might have said the wrong words to exspress my self

     

    First of all, a minor complaint. I am having trouble reading and understanding your post because of all the misspellings. Please try to do better (I know we aren't all perfect) so I can understand.

     

    Now, about what I think you said. Certainly the river ecology is an important consideration. A turbine does screw the the river ecology; its effect is not zero. To generate energy from the kinetic energy of the flow must slow the waterflow down. When all is said and done, there is always a tradeoff. Which is more harmful to the river ecology; one middle sized dam at only one point in the river or turbines throught the entire river plus a coal fired plant for when the river is dry/flood stage?

  3. Sure there were. They were called "wagons", and while they didn't use fossil fuels, they were actually *worse* in terms of energy efficiency because, well, there's no "off" switch on the horse or horses needed to pull them.

     

    The need to move large objects, or large quantities of objects, to very specific places (moreso than rail or boat, at least) has been around since the dawn of agriculture, and will continue long after cars are all electric. The issue is how to make those same vehicles more ecologically friendly and energy efficient.

     

    There certainly were pollution issues with horses that automobiles solved. Streets filled with horse manure knee-deep (every large city at the time had these conditions) does some nasty things to the local ecology. The gas-powered automobile solved this environmental disaster. We improved things then, we need to do so again now. I think we will get there, but I'm not sure what form the next generation of transport will come in (electric, biofuels, hybrids, other?).

  4. Have they invented fossil fuel free car yet? A car that runs on solar energy or electricity or something green?

     

    I know the answer is obviously 'yes' but I'm wondering how much milage can one get out of it and how cheap is it to use and maintain? In other words, would it be to the advantage of the average consumer to purchase one?

     

    Yes. In 1828. http://en.wikipedia.org/wiki/File:Jedlik%27s_electric-car.PNG

     

    For a more modern version, see what someone came up with in 1904: http://en.wikipedia.org/wiki/File:Bundesarchiv_Bild_183-1990-1126-500,_Kraftdroschke.jpg

     

    A better list can be found in: http://en.wikipedia.org/wiki/Electric_car

     

    To explain why electric hasn't caught on (yet) requires quite a bit of debate. Essentially, they cannot perform as well as a car powered by liquid fuel because the energy density of gasoline is so very much greater than what can be stored in a battery (per unit weight).

  5. for the fish to die they will ahve to be very samll to swimm throught a grate that protects the trubine from rubbish

     

    Thanks for pointing out this compromise and why a dam has an advantage over just the current flow in the river. For the turbine to not get clogged with debris (such as a very large tree; or an old tire) it needs to have a grate.

     

    Across a river, the grate will become clogged with debris; though it is cheaper and easier to clear the grate than replace turbine blades. As this occurs, the efficiency is reduced because there will be less water flow through the grate. Essentially, you now have to pay someone to clean the grate all the time; and it entirely likely that you will need to shut down the turbine while you do so.

     

    With a dam, the floating debris can simply stay on top of the water; above the turbine gates. The heavy debris can simply stay at the bottom; well below the turbine gates. There are very few things that naturally float in the middle; so the grate will remain clean for a very long time in comparison. Consequently, there is much less of a problem with debris clogging things up when using a dam.

  6. You are aware that nobody is seriously proposing just letting these people go, right? Just moving them to secure facilities in the mainland US.

     

    Umm...not true. Reread post # 30 and the link there (if it is still good). Now granted these individuals are probably more a threat to the Chinese than to us.

  7. At high altitudes, the thinner air results in a lower heat transfer from possibly hot components. As such, if there are components which may get hot, at high altitudes they might get too hot and either cause the device to shut down (as a built-in safety feature) or cause damage to the device.

  8. There isn't a clear definition of "alternative" medicines. Some have a logical reason why they could work, while others are really insane. To be fair we should judge each "alternative" medicine on its own merits.

     

    What JohnB is describing sounds like something people get from a chiropractor. This is one of the "alternative" medicines which often works (the treatments you get isn't much different than you would get from a physical therapist, IMO). Other "alternative" medicines people swear by includes the use of medical marijuana; again there are reasons to believe in this.

     

    I wouldn't class the above "alternatives" with some of the really crazy ideas out there.

  9. You raise a valid concern. However, how does the Escape Velocity of Earth compare with that of the Sun, from Earth's Orbit ??

     

    Isn't the latter basically Earth's Orbital Velocity ? And, isn't Earth's Orbital Velocity ~30 km/sec, or around 3x that of its Escape Velocity ?

     

    Moreover, don't Gravitational Potential Wells "add" or "super-impose" ? Thus, if you put the same planet, down deeper into a low-mass stars' Habitable Zone, havn't you actually twice-increased the Energy costs ?

     

    Interesting perspective, I'll have to give this some more thought. I was under the impression that as the spacecraft (once in earth orbit) is already travelling at 30 km/sec. So to go to mars, for example it needs to attain approximately the orbital velocity for mars, or about 24 km/sec.

     

    http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html

     

    Thus, wouldn't it only need an additional 6 km/sec to go from Earth to Mars? You've already done 11 km/sec to get off the earth. You aren't trying to escape from the sun, just to alter your orbit around the sun so you can go from one planet to the next. This isn't my best subject so please help me if I am missing something here?

  10. To the original poster: What kind of unknown and exciting properties would you think might be possible? I would speculate that even though the core is probably a solid, it might exhibit some kind of "flow" that would permit it to move similar to liquids. But this is pure speculation on my part.

     

    If only we could send a probe down there to take measurements and retrieve a sample for us. Of course, it would need to be made from unobtainium: http://en.wikipedia.org/wiki/Unobtainium

  11. i meant under water turbines to meet the under currunt it would work for a small community

    also dams dams may solve problems like floods and large scale electricity

    bu destroy lots of preasuse farm land pasture land woods ect

    dont destroy more land for electricity and money

     

    I'm not sure underwater turbines would work all that well, even for a small community. The efficiency is going to be low and there would the corresponding problems associated with river stages (flooding and drought would cause problems). There are going to be problems associagted with mud and debris clogging things up that are generally less of a problem with dams. But it is certainly possible to do, as long as you are willing to accept these costs (which is probably why this isn't seen very often).

     

    I do agree with you regarding the loss of land though it should at least be pointed out that a lake has been gained which compensates for the lost farms and forest.

  12. A dam solves lots of other practical issues.

     

    For the use of a generator in a riverbed, there is the problem that the water has to be flowing at the exact level to match the turbine. The water level in a river goes up and down all the time; so unless you want to be moving the (usually extremely large) turbines all the time, they won't be operating the majority of the time.

     

    With a dam, you can force the water to flow only on the exact "sweet spot" for the turbines. You can store excess water for use during the summer (when the river normally goes dry). During a flood, you can still operate the turbines; while letting the excess water go through the floodgates (if the turbines were only in the river, they would then be under water).

  13. ... Although the article blames only Republican, think the problems come from both party...

     

    With the Senate voting 90-6 against funding the shipment of the inmates here; obviously the problems come from both parties (Just as many Democrats as Republicans). That is unless 40 senators just decided to switch parties...:eek:

  14. Very Interesting CDarwin. More than 95% of the media coverage (at least in the USA) seems to give the impression of a desperate set of conditions in N. Korea. If true, the article puts the whole humanitarian aid thing into a different light. While very few people would oppose the sending of help for starving and freezing people; sending "aid" to people who don't really need it seems more like caving in to blackmail...

     

    So which story is correct? Perhaps the truth is somewhere in between?

  15. I've not met many people scared of the terrorists in our prisons. They (at least the people I've discussed this) are concerned that these Al Queda members will eventually be released from our prisons into the general population. They will eventually be released because due to the nature of their capture, the incompetence of the people at Gitmo (missing case files, etc.) and the need to preserve certain sources of information, etc. there aren't too many charges that will stand up in a court of law. Upon their release I doubt the nations these people are from (assuming we can even prove where they are from) will want them back, except perhaps to torture them, so they can only stay here.

     

    Also, many people who oppose them here do so out of general spite, not fear. They simply do not like these individuals and would prefer they rot somewhere else.

  16. Well, we now know what will happen to at least some of the inmates at Gitmo...they will be released as freemen within the USA.

     

    http://news.yahoo.com/s/bloomberg/20090603/pl_bloomberg/apmw9eac4ptu

     

    from the article:

    Some of the 17 Chinese Uighur Muslims being held at Guantanamo Bay, Cuba, will likely be released in the U.S. in an effort to convince other countries to accept prisoners from the detention facility, according to current and former American officials.

     

    The fate of the Chinese nationals, who were captured after the Sept. 11 attacks, has been a quandary for U.S. officials. While the Bush administration cleared the Uighurs for release or transfer between 2003 and 2008, the government hasn’t been able to find a country willing to accept them.

     

    I won't be holding my breath while we wait for other countries to step up and accept some of the inmates (though it is worth noting China was more than eager to accept these individuals ;) ) From the article

    China, which considers the Uighur detainees terrorists, has repeatedly urged their return. The U.S. hasn’t acceded to the request because the Uighurs “fear that if they are returned to China they will face arrest, torture or execution,” according to court papers.

     

  17. Oh please don't misunderstand, I really enjoyed the thought exercise. I've thought it through and for the reasons outlined above, I disagree with the assertion that space travel is more difficult for certain stars than for others; based simply on the fact that I think the variables I pointed out will dominate the variables Widdekind suggested.

     

    But I freely admit I could be totally wrong (and would welcome being proved wrong BTW) and in no way intended to throw cold water on these ideas. Its very clever, IMO, to try to deduce the consequences of stellar type with regards to space travel; I would never have thought of it! And his logic is indeed compelling.

  18. It does not address their point of missing/weird distress signals. Not that I believe the stories anyway ;)

     

    Well, in a catastrophic failure of the aircraft, the pilot might not have time/be able to send a distress signal (= missing). There was no distress signal by the pilot from the plane that recently went down off Brazil for example

     

    http://news.yahoo.com/s/ap/20090604/ap_on_re_la_am_ca/brazil_plane;_ylt=Aii6oLZtR7ZWBrKXZC0zztcDW7oF

     

     

     

    Some of the "weird" signals would include things like reports of a storm when there isn't a cloud in the sky...nevermind the plane is several hundred miles away :doh: Other "weird" signals would include the embellished reports (not all reporters, researchers, etc. have pure motives).

     

    Still, I agree there are things which are unanswerable. But that does not mean the reasons for this must be supernatural.

  19. Well, the whole idea behind the "bermuda triangle" and other similar "triangles" is that planes, ships, etc. seem to "disappear" more frequently there than in other locations. As such people believe that there must be a reason for this. However the conclusion that there must be something unusual about these locations is a logical fallacy...

     

    A phrase I like to use is "correlation does not equal causation"

     

    The rate of "unusual circumstances" does not happen in a steady basis for lots of reasons.

     

    One reason is that "streaks" can happen. Consider the flipping of a coin, heads or tails. Lets say that you are doing this all day. At 10:00 you happen to have a streak of 10 heads in a row. Would you conclude, "Wow, there is something unusual about 10:00?" You would if you did not realize that streaks happen. Likewise, a streak of accidents in a particular place might be considered unusual by someone who isn't really thinking this through.

     

    Another reason for these statements is peoples perception regarding these "unusual" events. In the tropics, especially during the summer, small thunderstorms can pop up very quickly. If a plane were to get caught in one of these and crashed, the news reporter might report clear skies at the airport where the plane took off...leading the reader to beleive the plane could not have crashed due to weather conditions. OR leave the reader to beleive something strange was happening as the weather was clear at the airport but stormy where the plane was (nevermind the plane is several hundred miles away). This would not be unusual, but would be believed to be unusual by the casual reader of the report.

     

    Of course, people who perhaps are trying to make a buck see these events as a good story and embellish upon it. So as such, some people in the public now hear (and quite possibly beleive) the "conspiracy theories" on "unusual" events "associated with a triangular region" and so forth.

     

    That's my explaination for all this anyway.

  20. The difficulty of space travel depends not necessarily on the gravity well you are climbing, but how high you are climbing it. It has been said "that once you are in orbit around the earth, you are halfway to anywhere" and the intent of this statement is that the earth is the deepest gravity well that most space probes have to leave.

     

    Thus, space travel is highly dependant on the size/gravity of the specific planet or moon it is launched from. I suspect this will be highly variable, and I don't see any reason why the stellar class would influence the planet size. (Edit: The reference provided in the wiki link isn't an internet address, so I couldn't read it; but the use of "suggests" in the wiki article means it isn't assured that the planets of M-type stars are smaller...Maybe the stellar type here has an influence, but I don't understand any reason why that would be the case so I will maintain the planets could be any size until either there is more data, or a scientific reason for habitable planets/moons being less massive...)

     

    The second variable is how much climbing of the stars gravity field to get to the planet/moon of interest. While a civilization might be deeper in the gravity well, so might the other planet of interest. Again, I am not aware of any reason why relative distances between planets and moons should be influenced by the stellar mass, so I suspect this too would be highly variable.

     

    Now as far as leaving the star itself, it could be harder for certain star types. But because the immense distances between stars (and the time required to travel this far) is a much, much greater obstacle; I don't see the stellar mass as being significant here either.

     

    For the above reasons, I would state that the stellar type would have much less influence than the variables above and therefore it is my opinion that space travel is not necessarily harder in any particular star type.

     

    Please correct me, however, if my understanding regarding my assumptions above (stellar type does not influence planetary mass or relative distances between planets) are not true.

  21. To reply to Pangloss (post # 21), I've heard the opposite (some commentator on the radio, can't remember who). His point was that the focus should be entirely on humanitarian aid and human rights in N. Korea. He felt the nuclear program was intended to be a distraction from the human rights crisis and that by ignoring the nuclear program, we take away their incentive to build it. Seemed to make sense to me.

  22. Doesn't anyone else think that a China acting unfriendly towards North Korea is better than a China acting too friendly towards North Korea?

     

    Perhaps. But as suggested previously, a collapse of N. Korea would be a bad thing. China could over-react and cause N. Korea to collapse; N. Korea is already quite desperate from all accounts. Think of an internal N. Korea civil war, millions of starving refuges in S. Korea; desperate people on rafts trying to reach Japan, being shot trying to enter China or Russia...all with a few nuclear weapons (including delivery systems) in the mix. This scenario isn't what anyone wants.

     

    That said, I think N. Korea has given the finger to everyone by their actions. While China (and I believe Russia) had been essentially supporting N. Korea's actions up till now, a real N. Korean nuclear program and delivery system program is a threat to everyone. As is the possibility of a N. Korean collapse. Therefore, China now needs to seriously address the situation.

     

    I think Russia can still afford to ignore the situation. But I don't see how an full-blown crisis in Korea benefits them, so I would expect them to be trying to calm the situation as well. Ironically, I would think the USA and EU could also afford to ignore the situation but they are the least likely to do so for humanitarian reasons.

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