View Poll Results: what do you think?
Hoss is da man, no
25
33.78%
Geico's question. He knows, yes
42
56.76%
your both wrong its a vto
7
9.46%
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will the plane fly?
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Joined: Dec 2003
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From: Minnesota
Originally Posted by gman07
OK
But what if you think about it this way: for a plane or any vehicle to move, with no wheel slip, the wheels turn. Lets say its a wheel with 6.28 ft circumference (2 ft diameter). It makes one rotation in 2 seconds. Doesn't that mean that any point on the outside of the wheel is moving at 3.14 ft/sec? I was assuming that this was the speed the conveyor would then move at, negating the plane's forward motion.
I really feel that everything I just said has been mentioned before several times, just like the "Take-off guys'" arguments. We are getting nowhere with this--we both feel we're right and no one is willing to budge or accept what the other is saying. I think it's best for us just to agree to disagree and stop wasting bandwidth
But what if you think about it this way: for a plane or any vehicle to move, with no wheel slip, the wheels turn. Lets say its a wheel with 6.28 ft circumference (2 ft diameter). It makes one rotation in 2 seconds. Doesn't that mean that any point on the outside of the wheel is moving at 3.14 ft/sec? I was assuming that this was the speed the conveyor would then move at, negating the plane's forward motion.
I really feel that everything I just said has been mentioned before several times, just like the "Take-off guys'" arguments. We are getting nowhere with this--we both feel we're right and no one is willing to budge or accept what the other is saying. I think it's best for us just to agree to disagree and stop wasting bandwidth
it all depends where the conveyor is picking up its speed reading.
your example has a rotational speed about the center at 1 rev/2 sec. the contact between the wheel and ground is zero otherwise ***EDIT: i took out what i didnt like*** no linear speed would result (your example is like a brake stand in a vehicle, there is rotational speed but no linear speed; ***EDIT: no linear speed = no conveyor activation), BUT we do have linear speed and the linear speed of the center of the wheel is the radius (1ft) x rotational speed or 1 ft/2 sec, and the linear speed of the top of the wheel is 2 radius's (2ft) x rotational speed or 1 ft/1 sec.
if the conveyor picks up the contact speed (zero) it will never activate. if it picks up the center speed the wheel rotates (0.5 ft/sec) it will activate at that speed. if it picks up the top-of-the-wheel speed (1 ft/sec) it will activate at that speed.
the only force we assumed is the force to allow the wheel to rotate. its free to rotate as much as it wants with no effect on the plane pulling itself through the air as the force to rotate the wheel is neglible and not holding the plane back.
again, i am assuming the conveyor is coming at you at takeoff per my interpretation of the problem and "opposite".
agree to disagree
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Joined: Nov 2001
Posts: 3,733
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From: Austria Europe
Well, the interesting thing is that the question in http://www.avweb.com/news/columns/191034-1.html is a little different.
According to their question the plane will fly, only a speedometer on the wheels would read twice as high on takeoff compared to the standard runway.
This question here is a little different- here it's assumed that the belt will match any wheelspeed but in the opposite direction- meaning if there is any wheelspeed it will be matched by the conveyor belt, which in turn will increase the wheelspeed etc- since the question does not say to eliminate friction and wheeldrag, and it does not assume an indestructible airplane etc it won't lift off, it will just have it's tires detonate due to overspeeding.
The original question as seen on the stated website is completely different.
AlpineRAM
According to their question the plane will fly, only a speedometer on the wheels would read twice as high on takeoff compared to the standard runway.
This question here is a little different- here it's assumed that the belt will match any wheelspeed but in the opposite direction- meaning if there is any wheelspeed it will be matched by the conveyor belt, which in turn will increase the wheelspeed etc- since the question does not say to eliminate friction and wheeldrag, and it does not assume an indestructible airplane etc it won't lift off, it will just have it's tires detonate due to overspeeding.
The original question as seen on the stated website is completely different.
AlpineRAM
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Joined: Nov 2002
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From: near Magnolia, Tx.
Ok .... for the benefit of the No-Fly guys .... let's tear apart the direction that the conveyor belt has to move to stop the wheels.
1. The wheels rely on the movement of the plane to rotate .... period. There is absolutely NO drive mechanism to make them move. Check online ... mabe howthingswork.com or something.
2. The only point of contact between the wheel and the ground / belt is the little tiny point on the bottom of the tire.
3. Now ... go jack your truck up in the air and have your significant other turn the drivers side wheel counter-clockwise ( refer to my previous post regarding the direction the plane is sitting and the direction the wheel would be turning).
4. Using your hand to counter the wheels rotation, and only touching the wheel on the bottom (refer to #2) ..... which direction would you be attempting to turn the wheel to make it stop ??
FROM THE RIGHT TO THE LEFT
**** Bear in mind that if you grab the wheel to stop it, you are simply acting as a brake and not countering the motion as the initial story states.
She's gonna fly .... again and again and again.
Come on back if you need beat up any more. I get paid for a 24 hour day and have LOTS OF TIME !!!
PISTOL
1. The wheels rely on the movement of the plane to rotate .... period. There is absolutely NO drive mechanism to make them move. Check online ... mabe howthingswork.com or something.
2. The only point of contact between the wheel and the ground / belt is the little tiny point on the bottom of the tire.
3. Now ... go jack your truck up in the air and have your significant other turn the drivers side wheel counter-clockwise ( refer to my previous post regarding the direction the plane is sitting and the direction the wheel would be turning).
4. Using your hand to counter the wheels rotation, and only touching the wheel on the bottom (refer to #2) ..... which direction would you be attempting to turn the wheel to make it stop ??
FROM THE RIGHT TO THE LEFT
**** Bear in mind that if you grab the wheel to stop it, you are simply acting as a brake and not countering the motion as the initial story states.
She's gonna fly .... again and again and again.
Come on back if you need beat up any more. I get paid for a 24 hour day and have LOTS OF TIME !!!
PISTOL
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Joined: Jan 2004
Posts: 138
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From: Maine
It pains me to have to point this out to you guy but......I TOLD YOU SO!!
I hate being right all the time.........he hee...
Originally Posted by Tengu
Wow! This is some serious discussion. I would like to ask this to the people that don't think that the plane will take off:
Since the earth is rotating at about 1000 MPH is it important to put the plane perpendicular to the direction of rotation? I mean hey if the ground is moving that fast than it would take 1000 extra MPH facing west than it would facing east right??????? Think again about the relativity thought experiments.
Tengu
Since the earth is rotating at about 1000 MPH is it important to put the plane perpendicular to the direction of rotation? I mean hey if the ground is moving that fast than it would take 1000 extra MPH facing west than it would facing east right??????? Think again about the relativity thought experiments.
Tengu
Originally Posted by Tengu
O.K. I am going to try ONE MORE TIME! Here ya go. All of the arguments about wheel speed are TRUE you are exactly correct except for one thing. The plane speed is INEDEPENDENT of the wheel speed. Think about it like this: The center of the wheel is not moving no matter how fast the wheel is spinning. When the plane engines start thrusting the thing that moves is the PLANE; it does not have ANY effect on the wheel speed. You could turn that conveyor up to 1,000,000 miles and hour and the plane would sit still (except for the very slight friction of the bearings. When the plane starts to move (Due to the thrust) it moves the only part of the wheel NOT ATTACHED TO WHAT IS ROTATING. Don't you see! AAAHhhhhhhggggggg.........
Originally Posted by Tengu
For the love of God man! There will NEVER be any "slip" between undrivin! freely rotating! well greased! wheels. They have no power to them. The ONLY time that the plane speed itself is affected by the wheel speed is when the BRAKES are applied.
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Joined: Apr 2004
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From: St.Paul , MN
awright. One more time. How about if the pilot realizing there is a hoax going on here, locks up the brakes and puts on the parking brake for good measure. IE wheels are not going to turn no how.
The conveyor exactly matches the wheel speed. Wheels no turnee, belt no movee.
Give it the throttle and spool up the jets. Plane starts moving...wheels no move....belt no move to match. plane goes faster and faster. v1 is reached wheels still no turn because belt is matching wheels. Pilot pulls back on stick and ...zoom airplane flys. wheels still not turning, belt not moving with wheels.
air plane flys no matter what.
The conveyor exactly matches the wheel speed. Wheels no turnee, belt no movee.
Give it the throttle and spool up the jets. Plane starts moving...wheels no move....belt no move to match. plane goes faster and faster. v1 is reached wheels still no turn because belt is matching wheels. Pilot pulls back on stick and ...zoom airplane flys. wheels still not turning, belt not moving with wheels.
air plane flys no matter what.
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Joined: Jan 2004
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From: Maine
A riddle (Not a "brain teaser"
O.k. three guys walk into a hotel to rent a room. The clerk says that will be $30. Each guy gives up $10 and the room is paid.
Later that evening the clerk realizes that they overpaid for the room. He calls the bellhop over and gives him a $5 bill and instructs him to give it to the guys. On the way up to the room he thinks "there are 3 guys and five dollars, how am I going to do this". So he gets 5 one dollar bills and gives each of them $1 and puts the other 2 in his pocket.
Now here is the question: If each guy gets a dollar back this means that they each paid $9, $10 - $1 = $9 with three guys this makes $9 x 3 = $27 plus the two that the bellhop put in his pocket, $27 + $2 = $29........Where is the other dollar?
Later that evening the clerk realizes that they overpaid for the room. He calls the bellhop over and gives him a $5 bill and instructs him to give it to the guys. On the way up to the room he thinks "there are 3 guys and five dollars, how am I going to do this". So he gets 5 one dollar bills and gives each of them $1 and puts the other 2 in his pocket.
Now here is the question: If each guy gets a dollar back this means that they each paid $9, $10 - $1 = $9 with three guys this makes $9 x 3 = $27 plus the two that the bellhop put in his pocket, $27 + $2 = $29........Where is the other dollar?
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Joined: Apr 2002
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From: Cypress, TX
Because the correct math is $30 originally paid minus $5 refund equals $25 for the room. $25 plus 3 x $1 refunded to each individual equals $28. Add the $2 that the bellhop kept and you have the $30. 
Rusty
Rusty
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Joined: Jun 2005
Posts: 685
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From: Southern IL
The "missing dollar" doesnt exist
$30 was in the drawer, and $5 was removed, leaving $25
Each guy was given $1 back, meaning they each paid $9
9x3=27
$25 in the drawer and $2 in the clerks pocket, that actually belongs in the drawer=$27
There is no $29 sum
$30 was in the drawer, and $5 was removed, leaving $25
Each guy was given $1 back, meaning they each paid $9
9x3=27
$25 in the drawer and $2 in the clerks pocket, that actually belongs in the drawer=$27
There is no $29 sum
