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Another Aeronautical (sort of) brain tickler
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You're in a car with the windows rolled up tight, the air vents shut and no fan running. The air inside the car is not moving at all. From a dead stop you accelerate to 60 mph in 4 seconds. Of course, you feel the sensation of being pulled back into your seat.
There is also a bug flying around inside the car when you accelerate. Is it pulled back to the rear window?
The first brain tickler is here. (And that answer is YES, the plane could take off.) THIS IS AN EDIT FROM ORIGINAL POST: I WAS WRONG IN THE ORIGINAL POST
(Last edited by design219; Mar 3, 2007 at 01:44 PM.
(Reason:I was incorrect!))
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Play Food Fight! available free on the App Store!
Or how about a really weird (or stupid) game: Nesen Probe, it's also free.
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Yes. The fly's mass is denser than the air.
Take it to a smaller scale. Put a fly in a balloon filled with air and shake it. The fly bounces all over the place.
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Wow, nailed that right off. Good analogy too. I think getting the fly into the balloon would be a bit tricky. 
(Last edited by design219; Mar 3, 2007 at 01:51 AM.
(Reason:typo))
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Play Food Fight! available free on the App Store!
Or how about a really weird (or stupid) game: Nesen Probe, it's also free.
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Clinically Insane
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No fair, Railroader clearly has a lot of experience ****ing with flies.
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Chuck
___
"Instead of either 'multi-talented' or 'multitalented' use 'bisexual'."
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Posting Junkie
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Originally Posted by design219 
The first brain tickler is here. (And that answer is no, the plane would not take off.)
Wrong. 
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Posting Junkie
Join Date: Oct 2005
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Originally Posted by design219
You're in a car with the windows rolled up tight, the air vents shut and no fan running. The air inside the car is not moving at all. From a dead stop you accelerate to 60 mph in 4 seconds. Of course, you feel the sensation of being pulled back into your seat.
There is also a bug flying around inside the car when you accelerate. Is it pulled back to the rear window?
The first brain tickler is here. (And that answer is no, the plane would not take off.)
Yes, the bug is going to splat the rear window due to inertia.
And the answer to the airplane-on-a-treadmill is that it would take off. Wheel speed has little meaning or consequence on vehicles that are not wheel powered.
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I went back to the other puzzler and re-read it. I was wrong, and stand corrected. The plane will take off. The "sitting on a runway" part threw me, but the question was just "can it take off." Barring any restraints, any plane capable of taking off, would.
analogika, you are right. 
And I feel a little slow.
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Play Food Fight! available free on the App Store!
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Originally Posted by design219
Wow, nailed that right off. Good analogy too. I think getting the fly into the balloon would be a bit tricky.
Thanks. It's not as hard as you think 
Originally Posted by Chuckit
No fair, Railroader clearly has a lot of experience ****ing with flies.
CRAP! I plead the fifth.
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Originally Posted by design219
I went back to the other puzzler and re-read it. I was wrong, and stand corrected. The plane will take off. The "sitting on a runway" part threw me, but the question was just "can it take off." Barring any restraints, any plane capable of taking off, would.
analogika, you are right.
And I feel a little slow.
Then perhaps you should go and edit your original post so that you don't have more people jumping on you for that?
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Professional Poster
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Originally Posted by design219
You're in a car with the windows rolled up tight, the air vents shut and no fan running. The air inside the car is not moving at all. From a dead stop you accelerate to 60 mph in 4 seconds. Of course, you feel the sensation of being pulled back into your seat.
There is also a bug flying around inside the car when you accelerate. Is it pulled back to the rear window?
Again, the solution to this problem, like the last, is to find out what forces are acting on the fly.
Assuming that the fly is just hovering in place at the moment, the only forces acting on it is the vertical force of its wings and the force generated by gravity. There is no horizontal force initially. When the car moves forward, everything in the car, including the air molecules, will be "pulled back" (actually nothing is being pulled, it just looks that way, everything is being pushed) towards the back of the car. This includes the fly.
Thus, while the car is accelerating forward, yes, the fly will go back, as will the air inside of the car (it will actually be denser towards the back, but just barely detectable at these speeds).
(Last edited by itistoday; Mar 3, 2007 at 12:59 PM.
)
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Clinically Insane
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Originally Posted by Chuckit
No fair, Railroader clearly has a lot of experience ****ing with flies.
-t
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Originally Posted by itistoday
everything in the car, including the air molecules, will be "pulled back" (actually nothing is being pulled, it just looks that way, everything is being pushed) towards the back of the car.
Neither of these statements is correct. Nothing is being pushed or pulled. The car's mass is accelerating. Due to inertial energy the mass of the objects in the car are not accelerating at the same rate.
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Originally Posted by Railroader
Neither of these statements is correct. Nothing is being pushed or pulled.
No, I believe you misunderstood me. The car's frame is pushing everything inside of it, which in turn is being pushed by the wheels. If it wasn't then the objects inside of the car would not move forward with the car (they would stay still in space and crash through the rear of the car, it would look very odd and everyone would be killed).
(Last edited by itistoday; Mar 3, 2007 at 02:08 PM.
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Originally Posted by itistoday
No, I believe you misunderstood me. The car's frame is pushing everything inside of it, which in turn is being pushed by the wheels. If it wasn't then the objects inside of the car would not move forward with the car (they would stay still in space and crash through the rear of the car, it would look very odd and everyone would be killed).
The car's frame is not "pushing" everything inside of it. The fly is certainly not being "pushed". If a steel ball happened to be in midair inside of the car at the moment that the car's acceleration occurred then it might crash through the rear window if the mass if it and the acceleration of the car was great enough.
Actually, the "pushing" is being done by the pistons in response to the explosions occurring inside of the cylinders.
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Originally Posted by Railroader
The car's frame is not "pushing" everything inside of it. The fly is certainly not being "pushed". If a steel ball happened to be in midair inside of the car at the moment that the car's acceleration occurred then it might crash through the rear window if the mass if it and the acceleration of the car was great enough.
Actually, the "pushing" is being done by the pistons in response to the explosions occurring inside of the cylinders.
See, again, you are misunderstanding me. That is not what I am saying. That steel ball will roll to the back but will be pushed by the frame of the car (or window) when it hits the back. The chairs, the air, everything in the car is being pushed by the frame. That is what I said and meant.
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Originally Posted by itistoday
See, again, you are misunderstanding me. That is not what I am saying. That steel ball will roll to the back but will be pushed by the frame of the car (or window) when it hits the back. The chairs, the air, everything in the car is being pushed by the frame. That is what I said and meant.
I am not misunderstanding you. You are using improper terms for a physics mental masturbation exercise.
Carry on.
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Originally Posted by Railroader
I am not misunderstanding you. You are using improper terms for a physics mental masturbation exercise.
Carry on.
I love you Railroader, arguing with you is such fun... literally I get the same satisfaction when talking to a wall. I read what you claim I said, see that it isn't what I stated or meant, tell you that, and you fight to the bitter end that that is not the case when it plainly is, just to save face. Carry on indeed.
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Originally Posted by itistoday
I love you Railroader, arguing with you is such fun... literally I get the same satisfaction when talking to a wall. I read what you claim I said, see it isn't what I stated or meant, tell you that, and you'll fight to the bitter end that that is not the case when it plainly is, just to save face. Carry on indeed.
Touche'
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