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Re:Tesla reveals Supercharger network, Free Fill Ups by kamaal on Tuesday September 25, 2012 @07:32AM (#4569757)
>>Well, how are you going to make the airplanes fly? Battery. Batteries are pretty heavy.

"Heavier than air flying machines are impossible"

-Lord Kevin.

Yet we have them today, thanks to a phenomenon in physics called Bernoulli's principle- http://en.wikipedia.org/wiki/Bernoulli%27s_principle

"The significant problems we face cannot be solved at the same level of thinking we were at when we created them" - Albert Einstein.

Why, O why do we think that problems have to, must be and will be solved at the same level and direction of thought the problems were framed in? Besides the whole point of a disruptive technology is that the solutions generally come as a bolt from the blue, completely surprising even the biggest experts in those areas. Directions from which those solutions come from are so radically different paths than originally they would come from. And this has not happened once, twice but many times.

Over confidence in science especially with regards to the negative aspects is not a good direction to begin with.

Re:Tesla reveals Supercharger network, Free Fill Ups by base698 on Tuesday September 25, 2012 @10:03AM (#4570352)
That's actually not how airplanes fly at all...

http://boards.straightdope.com/sdmb/showthread.php?t=22977

Re:Tesla reveals Supercharger network, Free Fill Ups by mikeash on Tuesday September 25, 2012 @10:16AM (#4570423)
Bernoulli's principle is indeed how airplanes fly. Your link shoots down the silly equal-time theory, not Bernoulli's principle.

Basically, airplanes fly for three reasons:

1. The wing deflects air downwards. 2. Air moves faster over the top of the wing than over the bottom. Much faster than the equal-transit theory indicates. 3. Air pressure is higher on the bottom of the wing than on the top.

The important thing that few people seem to grasp is that all three are equivalent statements. They aren't additive. There aren't three different reasons airplanes fly, there's one reason airplanes fly, with three different ways to look at it.

Re:Tesla reveals Supercharger network, Free Fill Ups by bulltale on Tuesday September 25, 2012 @02:00PM (#4571706)
This interesting. You say there is one reason airplanes fly. But "deflecting air downwards" is causing an lifting force by action=reaction (the way a rocket works) and "air pressure is higher on bottom of the wing than on the top" is causing a lifting force by pressure differences.

Those are different reasons, or am I mistaken here?

Re:Tesla reveals Supercharger network, Free Fill Ups by mikeash on Tuesday September 25, 2012 @02:11PM (#4571766)
Nope, they're completely inseparable. If you deflect air downwards, no matter how you do it, you must end up creating a pressure differential where air pressure is higher on the bottom than on the top. If you create such a pressure differential, then no matter how you do it, you'll end up deflecting air downwards.

Pressure is just a fancy way of saying force per area. The air pressure on the bottom of the wing is just the downward force exerted by the wing on the air, divided by the wing's area. The only way to deflect air is by applying a force to it, and the only thing applying a force to it is the wing.