Mythbusters to take on "the plane and the treadmill" conundrum?

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DanTMWTMP

Lifer
Oct 7, 2001
15,908
19
81
the only people that refuse the believe in the laws of the universe is Citrix, Smack down, and LS50 (sp). Why are you guys so dense? Just accept the truth, and move on. At first when I thought about it, I thought the plane wouldn't fly. After much thought, and reading other replies, it became severely obvious that the plane would indeed fly.
 

smack Down

Diamond Member
Sep 10, 2005
4,507
0
0
Originally posted by: Rob9874
It's like asking, "What if there were wheels on the top of the plane, and some kids were up there spinning them in the opposite direction than the plane is moving, would it move?" Of course it would! Why does the speed of the wheels spinning have anything to do with the plane moving? The wheels are free spinning, and are not attached to any drive train that thrusts the plane forward. They can spin backwards at infinite speed, and the plane can still move forward.

Go outside, put you car in neutral and spin one of the tires. See where the car goes.
 

Linflas

Lifer
Jan 30, 2001
15,395
78
91
Originally posted by: Citrix
Originally posted by: Linflas
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot. how hard is that to understand???

The treadmill is going 0 MPH as it is stationary in relation to both the ground and the atmosphere. The belt itself may be going 25MPH and the wheels on the plane are also going 25MPH but the plane itself is going 0 MPH in relation to the ground and the atmosphere. Pitch the props to provide thrust and the plane will begin to move forward. The link I provided back on the first or second page goes into great detail on how a propeller works.

and what happens when you throddle up and the treadmill also throddles up? you stay in the same spot.

No much like a screw being screwed into a wall the propeller will pull the plane forward through the air. Propellers used to be called airscrews for a good reason. If you can't grasp that simple concept then it is really a waste of time to continue to discuss this. It is like trying to describe color to someone that only sees black and white.
 

AbsolutDealage

Platinum Member
Dec 20, 2002
2,675
0
0
Originally posted by: Rob9874
It's like asking, "What if there were wheels on the top of the plane, and some kids were up there spinning them in the opposite direction than the plane is moving, would it move?" Of course it would! Why does the speed of the wheels spinning have anything to do with the plane moving? The wheels are free spinning, and are not attached to any drive train that thrusts the plane forward. They can spin backwards at infinite speed, and the plane can still move forward.

LOL, nice analogy.

I'm pretty sure that they are just trolling at this point.

Actually, I think that smack Down wasn't trolling, but now he has realized that he is wrong and has shut up out of embarassment.

EDIT: Whoops... looks like I spoke too soon for smack Down. So, what do you say about the hovercraft?
 

LS20

Banned
Jan 22, 2002
5,858
0
0
imagining an airplane on a Suspended treadmill cleared it up for me. conveyor belt != true ground
 

smack Down

Diamond Member
Sep 10, 2005
4,507
0
0
Originally posted by: DanTMWTMP
the only people that refuse the believe in the laws of the universe is Citrix, Smack down, and LS50 (sp). Why are you guys so dense? Just accept the truth, and move on. At first when I thought about it, I thought the plane wouldn't fly. After much thought, and reading other replies, it became severely obvious that the plane would indeed fly.

First of all the laws of the universe simple don't matter the question as posted ensures that the plane can't move forward because the speed of the wheels is matched by the treadmill result and zero net movement of the plane.

Second even under the laws of the universe there is nothing in them prevent the question from working as speficed.
 

Cerpin Taxt

Lifer
Feb 23, 2005
11,940
542
126
Originally posted by: Garth
Originally posted by: smack Down
Originally posted by: Rob9874
Originally posted by: Garth
Do you agree that were the nose of the plane tied to an immovable post in front of the treadmill, the plane would remain stationary while the treadmill moved underneath it?

I do, that's a good analogy. And then, would you agree if someone pulled that post forward, it would not also pull the plane forward, even though the treadmill was matching the speed of its wheels?

The plane can't move forward if the treadmill is matching the speed of the wheels. It is impossible to have movement under such a case.

We are not concerned about the speed of the wheels. We are concerned with the speed of the plane. Answer the question.

Well, smack Down??
 

LS20

Banned
Jan 22, 2002
5,858
0
0
Originally posted by: DanTMWTMP
the only people that refuse the believe in the laws of the universe is Citrix, Smack down, and LS50 (sp). Why are you guys so dense? Just accept the truth, and move on. At first when I thought about it, I thought the plane wouldn't fly. After much thought, and reading other replies, it became severely obvious that the plane would indeed fly.

because you have given it "much thought" and have read other replies when this is the first thread ive participated in regarding this subject?

way to be an asshole
 

JujuFish

Lifer
Feb 3, 2005
11,443
1,053
136
Originally posted by: smack Down
First of all the laws of the universe simple don't matter the question as posted ensures that the plane can't move forward because the speed of the wheels is matched by the treadmill result and zero net movement of the plane.
See my post earlier in this thread. Even in the scenario where the treadmill matches the rotational speed of the wheels, the plane can take off.
Second even under the laws of the universe there is nothing in them prevent the question from working as speficed.
You clearly do not understand physics, then. The only thing preventing the plane from moving forward is friction. That friction is negligible when it comes to preventing a plane from moving in real life.
 

DanTMWTMP

Lifer
Oct 7, 2001
15,908
19
81
Originally posted by: LS20
Originally posted by: DanTMWTMP
the only people that refuse the believe in the laws of the universe is Citrix, Smack down, and LS50 (sp). Why are you guys so dense? Just accept the truth, and move on. At first when I thought about it, I thought the plane wouldn't fly. After much thought, and reading other replies, it became severely obvious that the plane would indeed fly.

because you have given it "much thought" and have read other replies when this is the first thread ive participated in regarding this subject?

way to be an asshole

well, someone has to counter the assholery from you three :p.
Just read the replies, think about it for awhile. don't be so dense about it. right now you guys are just trolling, and hubris is getting in the way.

The first step to improving yourself is the realization that you are wrong
 

exdeath

Lifer
Jan 29, 2004
13,679
10
81
Originally posted by: Citrix
Originally posted by: Garth
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot.

Explain how the two bolded segments can be simultaneously true.


because the treadmill is negating that forward movement.

go run on a treadmill and the treadmill has a sensor that changes the speed of the treadmill if you move forward of the dead center of the belt. if you all of a sudden sprint and move forward the belt goes faster to push you back, you are stationary to the ground. now bolt on some wings to your shoulder will you fly?

No.

How about you have someone with a truck with a chain around your waist and the other end around the trucks bumper, and the person in the truck stomps the gas while you are doing this? Will you stay in place then? No?

Thrust from a planes engines are an external force that are completely independant of the wheels/treadmill system.
 

LS20

Banned
Jan 22, 2002
5,858
0
0
Originally posted by: DanTMWTMP
well, someone has to counter the assholery from you three :p.
Just read the replies, think about it for awhile. don't be so dense about it. right now you guys are just trolling, and hubris is getting in the way.

The first step to improving yourself is the realization that you are wrong

i just "got it" by imaginging a suspended conveyor/treadmill.

why call names when not everyone have spent a year discussing this matter on message boards?
 

smack Down

Diamond Member
Sep 10, 2005
4,507
0
0
Originally posted by: exdeath
Originally posted by: Citrix
Originally posted by: Garth
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot.

Explain how the two bolded segments can be simultaneously true.


because the treadmill is negating that forward movement.

go run on a treadmill and the treadmill has a sensor that changes the speed of the treadmill if you move forward of the dead center of the belt. if you all of a sudden sprint and move forward the belt goes faster to push you back, you are stationary to the ground. now bolt on some wings to your shoulder will you fly?

No.

How about you have someone with a truck with a chain around your waist and around the other end around the trucks bumper, and the person in the truck floors stomps the gas? Will you stay in place then?

Thrust from a planes engines are an external force that are completely independant of the wheels/treadmill system.

If the thrust from the engine is completely external to tthe wheels why do the wheels on an airplane spin when it is taking off?
 

Tom

Lifer
Oct 9, 1999
13,293
1
76
Originally posted by: Citrix
Originally posted by: Linflas
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot. how hard is that to understand???

The treadmill is going 0 MPH as it is stationary in relation to both the ground and the atmosphere. The belt itself may be going 25MPH and the wheels on the plane are also going 25MPH but the plane itself is going 0 MPH in relation to the ground and the atmosphere. Pitch the props to provide thrust and the plane will begin to move forward. The link I provided back on the first or second page goes into great detail on how a propeller works.

and what happens when you throddle up and the treadmill also throddles up? you stay in the same spot.


The force that makes the plane move is external to the treadmill, it is the propellor acting on the air. It's exactly the same as a person who is not on the treadmill pulling the airplane off the treadmill with a rope attached to the plane.

Do you think the whole wheel/treadmill speed issue would stop a person from pulling the plane off the treadmill ?

 

exdeath

Lifer
Jan 29, 2004
13,679
10
81
Originally posted by: smack Down
Originally posted by: exdeath
Originally posted by: Citrix
Originally posted by: Garth
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot.

Explain how the two bolded segments can be simultaneously true.


because the treadmill is negating that forward movement.

go run on a treadmill and the treadmill has a sensor that changes the speed of the treadmill if you move forward of the dead center of the belt. if you all of a sudden sprint and move forward the belt goes faster to push you back, you are stationary to the ground. now bolt on some wings to your shoulder will you fly?

No.

How about you have someone with a truck with a chain around your waist and around the other end around the trucks bumper, and the person in the truck floors stomps the gas? Will you stay in place then?

Thrust from a planes engines are an external force that are completely independant of the wheels/treadmill system.

If the thrust from the engine is completely external to tthe wheels why do the wheels on an airplane spin when it is taking off?

Friction.

When you roll a toy car on the ground using you hand instead of an engine inside the toy car, does it matter that the wheels on the toy car are spinning? Friction causes the wheels to spin as a result of your externally applied power, but it won't stop you from applying that power. The fact that the wheels are freely spinning due to friction of being in contact with the ground while you apply power and moving the car with your hand, has no bearing on where or how the power is being applied.
 

Linflas

Lifer
Jan 30, 2001
15,395
78
91
Originally posted by: smack Down
Originally posted by: exdeath
Originally posted by: Citrix
Originally posted by: Garth
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot.

Explain how the two bolded segments can be simultaneously true.


because the treadmill is negating that forward movement.

go run on a treadmill and the treadmill has a sensor that changes the speed of the treadmill if you move forward of the dead center of the belt. if you all of a sudden sprint and move forward the belt goes faster to push you back, you are stationary to the ground. now bolt on some wings to your shoulder will you fly?

No.

How about you have someone with a truck with a chain around your waist and around the other end around the trucks bumper, and the person in the truck floors stomps the gas? Will you stay in place then?

Thrust from a planes engines are an external force that are completely independant of the wheels/treadmill system.

If the thrust from the engine is completely external to tthe wheels why do the wheels on an airplane spin when it is taking off?

Please tell me you're just trolling and not really this ignorant?
 

LS20

Banned
Jan 22, 2002
5,858
0
0
Originally posted by: smack Down


If the thrust from the engine is completely external to tthe wheels why do the wheels on an airplane spin when it is taking off?

airplane on suspended conveyor belt. hand of god pulls on airplane, it moves at X air speed and X speed relative to the true ground. the conveyor magically matches X speed. so airplane continues to move at X speed relative to ground, and 2X speed relative to conveyor belt surface
 

DanTMWTMP

Lifer
Oct 7, 2001
15,908
19
81
Originally posted by: LS20
Originally posted by: DanTMWTMP
well, someone has to counter the assholery from you three :p.
Just read the replies, think about it for awhile. don't be so dense about it. right now you guys are just trolling, and hubris is getting in the way.

The first step to improving yourself is the realization that you are wrong

i just "got it" by imaginging a suspended conveyor/treadmill.

why call names when not everyone have spent a year discussing this matter on message boards?

i was mainly calling names @ smackdown for his ignorance and refusal to budge on the obvious.

elaborate on the suspended treadmill?
 

OutHouse

Lifer
Jun 5, 2000
36,410
616
126
Originally posted by: Linflas
Originally posted by: smack Down
Originally posted by: exdeath
Originally posted by: Citrix
Originally posted by: Garth
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot.

Explain how the two bolded segments can be simultaneously true.


because the treadmill is negating that forward movement.

go run on a treadmill and the treadmill has a sensor that changes the speed of the treadmill if you move forward of the dead center of the belt. if you all of a sudden sprint and move forward the belt goes faster to push you back, you are stationary to the ground. now bolt on some wings to your shoulder will you fly?

No.

How about you have someone with a truck with a chain around your waist and around the other end around the trucks bumper, and the person in the truck floors stomps the gas? Will you stay in place then?

Thrust from a planes engines are an external force that are completely independant of the wheels/treadmill system.

If the thrust from the engine is completely external to tthe wheels why do the wheels on an airplane spin when it is taking off?

Please tell me you're just trolling and not really this ignorant?


:Q i hope he is trolling....
 

smack Down

Diamond Member
Sep 10, 2005
4,507
0
0
Originally posted by: exdeath
Originally posted by: smack Down
Originally posted by: exdeath
Originally posted by: Citrix
Originally posted by: Garth
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot.

Explain how the two bolded segments can be simultaneously true.


because the treadmill is negating that forward movement.

go run on a treadmill and the treadmill has a sensor that changes the speed of the treadmill if you move forward of the dead center of the belt. if you all of a sudden sprint and move forward the belt goes faster to push you back, you are stationary to the ground. now bolt on some wings to your shoulder will you fly?

No.

How about you have someone with a truck with a chain around your waist and around the other end around the trucks bumper, and the person in the truck floors stomps the gas? Will you stay in place then?

Thrust from a planes engines are an external force that are completely independant of the wheels/treadmill system.

If the thrust from the engine is completely external to tthe wheels why do the wheels on an airplane spin when it is taking off?

Friction.

When you roll a toy car on the ground using you hand instead of an engine inside the toy car, does it matter that the wheels on the toy car are spinning? Friction causes the wheels to spin as a result of your externally applied power, but it won't stop you from applying that power.

So you claim that if there is no friction between the axel and wheel the planes wheels would not roll?
 

JujuFish

Lifer
Feb 3, 2005
11,443
1,053
136
Originally posted by: smack Down
Originally posted by: exdeath
Friction.

When you roll a toy car on the ground using you hand instead of an engine inside the toy car, does it matter that the wheels on the toy car are spinning? Friction causes the wheels to spin as a result of your externally applied power, but it won't stop you from applying that power.

So you claim that if there is no friction between the axel and wheel the planes wheels would not roll?

The friction is between the wheels and the treadmill. Please tell me you're trolling.
 

OutHouse

Lifer
Jun 5, 2000
36,410
616
126
Originally posted by: smack Down
Originally posted by: exdeath
Originally posted by: smack Down
Originally posted by: exdeath
Originally posted by: Citrix
Originally posted by: Garth
Originally posted by: Citrix
Originally posted by: Number1
Has anybody in the "it will not fly" camp read sao123's post? That would be a start to get a good understanding of the problem and it?s solution.
The speed of the plane is in relation to the ground. If the plane is not moving in relation to the ground, the treadmill is not moving. If the plane is moving at 25 MPH in relation to the ground, the treadmill is moving at 25 MPH in the opposite direction. The prop moves the plane trough the air. The treadmill rotates the wheels. The plane accelerates and takes off.

i read it and it still does not explain where the wind comes from to get that lift. if the plane is going 25mph west and the treadmill is going 25mph east the plane is not moving. sure the wheels are but the plane is staying in one spot.

Explain how the two bolded segments can be simultaneously true.


because the treadmill is negating that forward movement.

go run on a treadmill and the treadmill has a sensor that changes the speed of the treadmill if you move forward of the dead center of the belt. if you all of a sudden sprint and move forward the belt goes faster to push you back, you are stationary to the ground. now bolt on some wings to your shoulder will you fly?

No.

How about you have someone with a truck with a chain around your waist and around the other end around the trucks bumper, and the person in the truck floors stomps the gas? Will you stay in place then?

Thrust from a planes engines are an external force that are completely independant of the wheels/treadmill system.

If the thrust from the engine is completely external to tthe wheels why do the wheels on an airplane spin when it is taking off?

Friction.

When you roll a toy car on the ground using you hand instead of an engine inside the toy car, does it matter that the wheels on the toy car are spinning? Friction causes the wheels to spin as a result of your externally applied power, but it won't stop you from applying that power.

So you claim that if there is no friction between the axel and wheel the planes wheels would not roll?

<<< runs out of thread like Richard Pryor on fire.
 

smack Down

Diamond Member
Sep 10, 2005
4,507
0
0
Originally posted by: JujuFish
Originally posted by: smack Down
Originally posted by: exdeath
Friction.

When you roll a toy car on the ground using you hand instead of an engine inside the toy car, does it matter that the wheels on the toy car are spinning? Friction causes the wheels to spin as a result of your externally applied power, but it won't stop you from applying that power.

So you claim that if there is no friction between the axel and wheel the planes wheels would not roll?

The friction is between the wheels and the treadmill. Please tell me you're trolling.

So now why when the treadmill rolls the wheel backwards does not that same friction apply? Does it not turn the wheel in the oppisite direction? Does that wheel turning not apply a force to the plane?