A plane on a runway, how smart is r3vlimited?

[Justin B]

s0urce, that'll work too, I guess :D

rwdrift, there's been some really good explanation in the thread. Did you read my post? The plane will move forward, the conveyor belt which really isnt helping or hurting matters is going backwards. The only difference is that the wheels spinning along by themselves are experiencing twice as many RPM as they should be.

[s0urce]

s0urce, that'll work too, I guess :D

rwdrift, there's been some really good explanation in the thread. Did you read my post? The plane will move forward, the conveyor belt which really isnt helping or hurting matters is going backwards. The only difference is that the wheels spinning along by themselves are experiencing twice as many RPM as they should be.

You are correct sir. The engines drive the plane against the air around the plane. The engines do not drive the wheels.

[Axxe]

VERY GOOD! Yes, the ball has to displace MORE water when it is in the boat cause it weighs MORE than water. So it must displace a VOLUME of water equale to it's weight. When it's on the bottem of the pool - it's resting on the bottem - and it only displaces it's VOLUME (NOT the the VOLUME of water equale to it's weight)

Hmm, correct, I forgot to look at the physical volume part. However, it is dependant on the density of the ball, if we are assuming it is more dense than water (which it probably is), then my original response was incorrect. I didn't think about it, I just posted my instinct, which was kinda close, but not really. Also, consider that the slight difference will likely be unmeasurable :)

[Erick]

s0urce, that'll work too, I guess :D

rwdrift, there's been some really good explanation in the thread. Did you read my post? The plane will move forward, the conveyor belt which really isnt helping or hurting matters is going backwards. The only difference is that the wheels spinning along by themselves are experiencing twice as many RPM as they should be.

I think I can picture what you are saying..... but it's 2:26am and there is no way my mind can function at this time.

Leave a message after the beep.

- Erick






























PS: On a serious note, I can clearly picture what you are saying. Most explanations (if indeed most people who said yes understand it themselves) aren't the clearest. I am still unsure whether or not that would work because then you'd need a conveyor belt the size of a runway... and you'd have to be able to calculate the wheel drag... but then again how would the belt calculate the speed of the plane..... ahhhhhhhhhhhhhh i'm going crazy again. Usefulness ends here.

IT"S BUSH'S FAULT!

[Borat]

OK, another water question...
a glass of water filled to top has an ice cube sitting in it, what happens when the ice melts? does the water drop, stay the same, or rise?

[Erick]

Depends how much of the ice is sticking out of the water? The more ice is out of the water, the higher the water level will rise when that ice melts.

Unless of course density has something to do with it, since ice is less dense than water (liquid form), which at this point I cannot even process any relation.... even as obvious as it might be.

I should really go to sleep now.

- Erick

[Justin B]

I am still unsure whether or not that would work because then you'd need a conveyor belt the size of a runway...

THAT is the whole point!!! :) Its a trick question, people don't see that, obviously they would need a belt the length of the runway. I myself wanted to believe it was just a belt the length of the plane itself and thought for a while till I finally saw it. You got it now. Regardless of whether the "belt" is going half the speed of the airplane, or twice the speed of the plane, the plane is still pulling itself forward because the wheels are not creating enough drag to hold it back just by rolling resistance. All they're doing is keeping the landing gear from collapsing under the plane, its their whole job whether the ground is at rest or not.

[george graves]

OK, another water question...
a glass of water filled to top has an ice cube sitting in it, what happens when the ice melts? does the water drop, stay the same, or rise?

I know this one - so I'll refrain.

[tonytony]

i skip a couple of pages and we're on the subject of ice now? wtf bah i'm drunk. I still think the plane will take off, just for shits and giggles did someone email myth busters yet?

[Justin B]

Damnit, I had a whole answer written out,I posted it, then I deleted it because I wasn't sure.

The water level stays the same though, and thats my final answer. I'll just stick with what I thought before. The little bit of air that is in the ice allows a little bit of the ice to poke out of the water, but once the ice cube is melted, the water that was sticking out will make up for the air content in the ice when it was still solid. Resulting in 0 rise or loss. Its basically the density of water vs density of water.

Am I right? =/

[joshh]

Water expands when it freezes. So I'd have to say the glass would be a tad less after it melted.

[Justin B]

Yes, thats why I deleted my post I didnt even want to bother answering it after I kept thinking about it, but ended up reposting anyway. Ice expands, true, but there is air in there, its not solid water all the way through. When things get cold they usually contract, how would ice expand if there wasnt air in it? Thats why it does. Anyways, when its in the glass there is air below the water line, once it melts, that air is displaced by the water content (much more than that of the air content, thats why its mostly sunk) of the ice sticking out of the top of the water line. Thats where I'm getting my idea from. The whole glass isn't ice :)

[george graves]

No - the post didn't say there is "air in the ice" - ASSUME A SOILD PEICE OF ICE! No Air bubble what so ever.

(and no - Ice does not expand "cause there Air in there")

[erik325i]

Water expands when it freezes. So I'd have to say the glass would be a tad less after it melted.

But you are forgetting about the little bit of ice poking out of the top of the water (because ice floats).

I'm with Justin. I think the water will stay the same level.

-Erik

[tonytony]

the water will stay the same level, i've done this expirement.