# Will the Plane Take-Off - Merged with MythBusters Show Thread

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**121**Creepy guy in the mirror.

NSXNEXT.

The whole time I am thinking "he is smarter than this, why cant he figure this one out". I mean in most of your other posts you sound smart.

I shoulda figured you were screwing with us.

hahah

The whole time I am thinking "he is smarter than this, why cant he figure this one out". I mean in most of your other posts you sound smart.

I shoulda figured you were screwing with us.

hahah

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**123**Interesting. Interesting.

Originally Posted by

**JLatimer**The whole time I am thinking "he is smarter than this, why cant he figure this one out". I mean in most of your other posts you sound smart.

I shoulda figured you were screwing with us.

hahah

Really? The whole time I was thinking "Same old same old for NSXNEXT"

edit: Meaty Beety Big & Bouncey > wstevens

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Originally Posted by

**BEETROOT**The plane wouldn't be stationary.

Think of the propulsion of the engines as a rope pulling the plane forward. It makes no difference how the wheels are spinning underneath. The plane wouldn't sit there still and then all of a sudden take off. It would move forward in pretty much the same way it would on a solid runway, just the tires would be spinning faster.

btw you can google to find the answer...

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**129**You want me to break it?

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I haven't read page 4-5 yet. Planes need air movement over their wings to generate lift - air moves faster over the upper surface than it does over the lower one so the plane gets sucked up (or pushed up from the bottome) into the air by its wings was my understanding.

If you have a perfect treadmill that will match the plane's wheel speed exactly, the plane will have no forward motion relative to a stationary reference point. All this arguing about thrust is pointless - thrust is just there to give the plane forward motion and generate air flow over the wings. An icy surface only matters if the "thrust" is generated by the wheels which it isn't in a plane so that doesn't matter either?

Bottom line - without enough airflow over the wings which is dependent on the plane actually moving (which it cannot do on a perfect treadmill) the plane shouldn't go anywhere. It might need some new tires/bearings, but it isn't going up.

The one exception might be if the thrusters were in front of the wings for some ungodly reason and could generate the required airflow without the plane actually moving forward while on the treadmill- then the plane could take off and once it left the treadmill it would shoot off like a rocket I think - might be wrong though.

If you have a perfect treadmill that will match the plane's wheel speed exactly, the plane will have no forward motion relative to a stationary reference point. All this arguing about thrust is pointless - thrust is just there to give the plane forward motion and generate air flow over the wings. An icy surface only matters if the "thrust" is generated by the wheels which it isn't in a plane so that doesn't matter either?

Bottom line - without enough airflow over the wings which is dependent on the plane actually moving (which it cannot do on a perfect treadmill) the plane shouldn't go anywhere. It might need some new tires/bearings, but it isn't going up.

The one exception might be if the thrusters were in front of the wings for some ungodly reason and could generate the required airflow without the plane actually moving forward while on the treadmill- then the plane could take off and once it left the treadmill it would shoot off like a rocket I think - might be wrong though.

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**130**Yeehaw

Originally Posted by

**Nineteen** How does the plane move forward via the wheels if the conveyor belt is moving in the opposite direction?

I think if you read the thread you will find most questions like this have been answered... but, the plane doesn't move forward via the wheels. It moves via the thrust of the engines... no connection to the wheels, the ground, or the conveyor belt.

Imagine if the wheels had zero friction, and the conveyor belt was moving 100mph. The wheels would spin, but the plane would not move. Now the plane engages the engines, and it moves forward exactly as it would on solid ground.

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Originally Posted by

**GIBSON6594**if a tree falls in the woods and there is no one around to hear it, does it make any noise?

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**134****Senior Moderator**

Originally Posted by

**BEETROOT**This was fun. Anyone got another one?

A boy is 10 feet from a wall, and throws a ball against the wall. As the ball travels towards the wall, the distance between the ball and the wall is cut in half (the ball is 5 feet from the wall), then that distance is cut in half again (now the ball is 2 1/2 feet from the wall), and so on and so on.....

How many times is the distance cut in half before the ball reaches the wall? EVen when the ball is as close as a fraction of a inch from the wall, that distance must still be cut in half before the ball can reach the wall. And as we know, the ball does eventually hit the wall. So how many times was the distance cut in half?

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I'm not even going to begin to get involved in this debate.

But I gotta put in my

As much thrust as the plane produced, it could 1000 lbs, 10000, 1,000,000 lbs I don't care, thrust doesn't make a plane fly, lift does. Thrust is used to move the plane on the ground and keep it in motion in air. But the thrust is needed to get the air moving over the wings to produce lift. If the plane is stationary, which it obviously is, their isn't going to be any air going over the wings so no lift is produced. so no takeoff. The conveyor belt doesn't move the air.

But I gotta put in my

As much thrust as the plane produced, it could 1000 lbs, 10000, 1,000,000 lbs I don't care, thrust doesn't make a plane fly, lift does. Thrust is used to move the plane on the ground and keep it in motion in air. But the thrust is needed to get the air moving over the wings to produce lift. If the plane is stationary, which it obviously is, their isn't going to be any air going over the wings so no lift is produced. so no takeoff. The conveyor belt doesn't move the air.

**it counteracts the thrust.**
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Originally Posted by

**fdl**Is infinity a real, fixed number? Does it exist? And if so, what is it?

A boy is 10 feet from a wall, and throws a ball against the wall. As the ball travels towards the wall, the distance between the ball and the wall is cut in half (the ball is 5 feet from the wall), then that distance is cut in half again (now the ball is 2 1/2 feet from the wall), and so on and so on.....

How many times is the distance cut in half before the ball reaches the wall? EVen when the ball is as close as a fraction of a inch from the wall, that distance must still be cut in half before the ball can reach the wall. And as we know, the ball does eventually hit the wall. So how many times was the distance cut in half?

A boy is 10 feet from a wall, and throws a ball against the wall. As the ball travels towards the wall, the distance between the ball and the wall is cut in half (the ball is 5 feet from the wall), then that distance is cut in half again (now the ball is 2 1/2 feet from the wall), and so on and so on.....

How many times is the distance cut in half before the ball reaches the wall? EVen when the ball is as close as a fraction of a inch from the wall, that distance must still be cut in half before the ball can reach the wall. And as we know, the ball does eventually hit the wall. So how many times was the distance cut in half?

Infiniti is not a true number because it is only defined as the non-existance of a final number.

Interestingly, the second one is infinity. Yes, the ball will hit the wall eventually but mathematically you can keep cutting numbers in half forever.

So what is the real answer?

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**138**Nom Nom Nom Nom

Originally Posted by

**fdl**, it will not take off. As its been mentioned, there will be air flowing over the wings and therefore no lift.

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Originally Posted by

**fdl**And as we know, the ball does eventually hit the wall. So how many times was the distance cut in half?

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Originally Posted by

**Whiskers**Im horny....

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**143****Senior Moderator**

Originally Posted by

**RLToni**Warning!! Complete Guess following:

Infiniti is not a true number because it is only defined as the non-existance of a final number.

Interestingly, the second one is infinity. Yes, the ball will hit the wall eventually but mathematically you can keep cutting numbers in half forever.

Infiniti is not a true number because it is only defined as the non-existance of a final number.

Interestingly, the second one is infinity. Yes, the ball will hit the wall eventually but mathematically you can keep cutting numbers in half forever.

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**144**Nom Nom Nom Nom

Originally Posted by

**fdl**Is infinity a real, fixed number? Does it exist? And if so, what is it?

A boy is 10 feet from a wall, and throws a ball against the wall. As the ball travels towards the wall, the distance between the ball and the wall is cut in half (the ball is 5 feet from the wall), then that distance is cut in half again (now the ball is 2 1/2 feet from the wall), and so on and so on.....

How many times is the distance cut in half before the ball reaches the wall? EVen when the ball is as close as a fraction of a inch from the wall, that distance must still be cut in half before the ball can reach the wall. And as we know, the ball does eventually hit the wall. So how many times was the distance cut in half?

A boy is 10 feet from a wall, and throws a ball against the wall. As the ball travels towards the wall, the distance between the ball and the wall is cut in half (the ball is 5 feet from the wall), then that distance is cut in half again (now the ball is 2 1/2 feet from the wall), and so on and so on.....

How many times is the distance cut in half before the ball reaches the wall? EVen when the ball is as close as a fraction of a inch from the wall, that distance must still be cut in half before the ball can reach the wall. And as we know, the ball does eventually hit the wall. So how many times was the distance cut in half?

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**145****Senior Moderator**

Originally Posted by

**fla-tls**We know that? I don't think the ball will hit the wall. I refer back to the infinity section of your question. That's the number of times you'd have to cut the distance in half.

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**147****Senior Moderator**

Originally Posted by

**SwervinCL**Yes it does. I was wrong too. I thought the same thing as you. But the plane will take off normal. The only difference is that the wheels will be spinning twice as fast as normal.

Its impossible. Unless you can explain to me how lift is acheived. If the plane is not moving through the air, it will not take off.

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Originally Posted by

**fdl**Yes but since the ball hit the wall, that means that at some point the distance could not be cut in half any longer. I.E. the distance was zero.

1/1=1

1/2=.5

1/3=.3333333

etc.

Never. It keeps getting infinitely closer to 0, but never becomes it. I don't think the ball will ever hit the wall. If it does - I'll be too old to care.

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**149**Nom Nom Nom Nom

Originally Posted by

**fdl** Its impossible. Unless you can explain to me how lift is acheived. If the plane is not moving through the air, it will not take off.

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**150**Nom Nom Nom Nom

Originally Posted by

**fla-tls**That's like asking "When will the result of the function of 1/X be zero?"

1/1=1

1/2=.5

1/3=.3333333

etc.

Never. It keeps getting infinitely closer to 0, but never becomes it. I don't think the ball will ever hit the wall. If it does - I'll be too old to care.

1/1=1

1/2=.5

1/3=.3333333

etc.

Never. It keeps getting infinitely closer to 0, but never becomes it. I don't think the ball will ever hit the wall. If it does - I'll be too old to care.

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**151****Senior Moderator**

Originally Posted by

**fla-tls**That's like asking "When will the result of the function of 1/X be zero?"

1/1=1

1/2=.5

1/3=.3333333

etc.

Never. It keeps getting infinitely closer to 0, but never becomes it. I don't think the ball will ever hit the wall. If it does - I'll be too old to care.

1/1=1

1/2=.5

1/3=.3333333

etc.

Never. It keeps getting infinitely closer to 0, but never becomes it. I don't think the ball will ever hit the wall. If it does - I'll be too old to care.

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Originally Posted by

**fdl**...Are you saying that if you throw a ball against a wall it wont hit the wall? of course it will

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**153****Senior Moderator**

Originally Posted by

**SwervinCL**Read the last 5 pages. The wheels have nothing to do with forward movement on a plane. The thrust produced from the engines will make the plane move forward reguardless of the speed the ground is moving at.

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**157**Nom Nom Nom Nom

Originally Posted by

**fdl**Ok, well as long as the plane is actually moving forward, then lift can be acheived. I assumed the conveyor was countering its forward motion. Its a trick question

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**159**So, do you like...stuff?

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Originally Posted by

**fdl** Its impossible. Unless you can explain to me how lift is acheived. If the plane is not moving through the air, it will not take off.

Look, the second the engines spool up and the plane slowly creeps forward (which in turn causes the conveyor to move backwards in the opposite direction), its too late! The plane has already started moving forward. The conveyor just reacted instantly to the forward motion. The end result is that the plane accelerates faster and faster forward while the conveyor accelerates (faster and faster)x2 in the opposite direction.

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**160****Senior Moderator**

Originally Posted by

**RogerPodacter**The plane IS moving thru the air in a forward direction.

Look, the second the engines spool up and the plane slowly creeps forward (which in turn causes the conveyor to move backwards in the opposite direction), its too late! The plane has already started moving forward. The conveyor just reacted instantly to the forward motion. The end result is that the plane accelerates faster and faster forward while the conveyor accelerates (faster and faster)x2 in the opposite direction.

Look, the second the engines spool up and the plane slowly creeps forward (which in turn causes the conveyor to move backwards in the opposite direction), its too late! The plane has already started moving forward. The conveyor just reacted instantly to the forward motion. The end result is that the plane accelerates faster and faster forward while the conveyor accelerates (faster and faster)x2 in the opposite direction.

As long as the plane is actually moving, I'm with you. So at some point i guess the plane would move forward off the conveyor as well. Assuming the conveyor was not "infininately" long