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Movie plot device

Discussion in 'Off Topic' started by jgs, Mar 10, 2015.

  1. jgs

    jgs Member

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    I want to see this in a movie some time: Car chase. Bad guy gaining. Has a faster vehicle. But then! We enter the anoxic environment. (Why is it anoxic? I have no idea. And for that matter maybe it's vacuum or maybe it's just got an anoxic atmosphere. Whatever.) Ha! The bad guy is driving an ICE (or even a FCEV). It sputters and dies. The good guy's BEV cruises to safety.

    The BEV could be a Tesla, but it would be funnier if it were a Smart ForTwo. But really it would probably be whatever brand paid for the product placement.

    I suppose the good guy has to have a way to breathe, too. Do I have to do ALL the work around here?
     
  2. rolosrevenge

    rolosrevenge Dr. EVS

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    This sounds overly complicated. I'm also not sure how this situation could even be fictionally encountered.
     
  3. jgs

    jgs Member

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    1. You must not have watched many action movies in the last few decades? Implausibility doesn't seem to be any barrier.
    2. There's a reason I posted in the "off topic" area, I wasn't intending to be profound, more to amuse.
     
  4. ggr

    ggr Roadster R80 537, SigS P85 29

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    Villages have died because of an eruption of CO2 from lakes. There is pretty solid speculation that there could be increasing numbers of methane eruptions. The latter might give you an even worse movie plot device: a ring of fire around the boundary of the eruption where the methane and air mix, perhaps set off by the points in an old car? Or maybe the driver is just smoking? I can't think of any way a modern car would set fire to a methane-air mix, unless it was about to catch fire anyway.
     
  5. jgs

    jgs Member

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    Aren't movie cars always about to catch fire, and that's why they go up in spectacular fireballs at the drop of a hat?
     
  6. Saghost

    Saghost Active Member

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    It's not that hard. What if a propane or liquid nitrogen tanker lost containment in one of the underground/underwater tunnels? (Lincoln tunnel into New York, either of the Baltimore tunnels, etc.)

    The propane is heavier than air, so it would just sit there, displacing all of the air until the fans can remove it - the liquid nitrogen would boil off as it warms and create a cold layer of nearly pure nitrogen that would tend to sit there as well.

    Because of how easily this can happen to underground/underwater tunnels, those types of trucks aren't supposed to be in those tunnels if they follow the rules...

    (Of course, you do realize that the protagonist in your plan needs some way to keep breathing, right? They can maybe gain a little time by turning off the HVAC, but they probably need an oxygen tank and either masks or a way to isolate/pressurize the cabin.)
    Walter
     
  7. jgs

    jgs Member

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    Well done, that's perfect.

    Yes, I did note that up front though I didn't propose a solution. If they happened to have a scuba tank in the back seat they could crack the valve and that would probably do the trick. But if the cabin is moderately air tight, it looks like the trapped air will be enough.

    Per some random page on the Internet (Friday Fiction Facts: Trapped in an airtight room! | Endless Forms Most Beautiful) the equation we want is

    Time Our Hero can survive = (volume of air in cu ft) * 0.03 / (number of people * hourly production of CO2 per person).

    Let's suppose Our Hero is alone. A Tesla Model S (why not) has a volume of 93 cubic feet and a person under stress produces CO2 at a rate of 1.7 cu ft per hour (same reference). So:

    T = (93 * 0.03) / (1 * 1.7) = 1.64 hours!

    Come to think of it, this is consistent with the intuition we might take from considering that a typical scuba tank (a so-called "aluminum 80") holds a nominal 80 cubic feet of air at STP. Of course, with scuba you don't have to worry about accumulating CO2, but the similarity of the numbers is still comforting. So we can even chuck a sidekick in, derate all our numbers by 50% because it's not really air tight, and still have 25 minutes to get out of the tunnel, all without adding a scuba tank. With a smaller car (that Smart ForTwo) we have to get them out of the tunnel quicker, but we weren't going to leave them in there for 25 minutes anyway. In the mean time, I am pretty sure the ICE car engine is going to stop working within seconds of entering the tunnel. (Not sure about a FCEV, but it seems likely that it would choke just about as fast.)
     
  8. BerTX

    BerTX Member

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    Bond's underwater Tesla would have supplemental breathing built in.
     

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