Thanks Al but we know that. Now take your thinking to the next step and concentrate on the wheels, the belt and how progress, if any, can be made if the two are turning at the same speed.
Hint: This has nothing to do with the thrust being able to overcome anything. If you continue down that path you won't arrive at the answer. Once you see that with wheel and belt speed being equal, progress is impossible, and you'll realize you don't even have to factor the thrust into the equation. The thrust only creates an infinite wheel speed, not progress.
Hint: This has nothing to do with the thrust being able to overcome anything. If you continue down that path you won't arrive at the answer. Once you see that with wheel and belt speed being equal, progress is impossible, and you'll realize you don't even have to factor the thrust into the equation. The thrust only creates an infinite wheel speed, not progress.
OK Cal, lets take another angle - Conservation of Momentum.
You accept the principle that the thrust of the engine pushes the plane forward. If the plane does not move, where is this energy going?
You accept the principle that the thrust of the engine pushes the plane forward. If the plane does not move, where is this energy going?
Hi Cal,
First I'd like to say this. I would not want any political leader to stay in my neck of the woods. I just happen to know Jack is there.
That is the point I think you are missing. But let's argue the dark side of things
young Luke, I mean Cal. 😀 What if the belt moves to oppose the motion of the wheels. i.e. the wheels are stationary. The belt is completely free to move with respect to the earth, wind, sky. .. Therefore the motion of the fuselage is not hampered in any way, it's free to react to the thrust of the engines. The planes leaves on schedule. 
Tire wear greatly reduced. 😀
-Chris
First I'd like to say this. I would not want any political leader to stay in my neck of the woods. I just happen to know Jack is there.
That is the point I think you are missing. But let's argue the dark side of things
young Luke, I mean Cal. 😀 What if the belt moves to oppose the motion of the wheels. i.e. the wheels are stationary. The belt is completely free to move with respect to the earth, wind, sky. .. Therefore the motion of the fuselage is not hampered in any way, it's free to react to the thrust of the engines. The planes leaves on schedule. Tire wear greatly reduced. 😀-Chris
OK, so... If the belt speed must match the wheel speed in order to keep the plane stationary relative to a fixed point on the ground then, surely, if the belt moved faster than the wheels the plane would go backwards wouldn't it?
The plane is stationary relative to a position on the belt machinery (not the belt itself). The plane, it's wheels and the belt machinery all hurtle along the ground until the plane takes off.
The pilot knowing that the enormous and heavy belt must match the speed of the wheels locks the brakes on the wheels immediately after take off stopping them instantly. The inertia of the much larger and heavier belt causes it to self destruct.
A fitting end to an oppresive regime.....All hail the plane....hail!
The pilot knowing that the enormous and heavy belt must match the speed of the wheels locks the brakes on the wheels immediately after take off stopping them instantly. The inertia of the much larger and heavier belt causes it to self destruct.
A fitting end to an oppresive regime.....All hail the plane....hail!
How come moderators get to talk politics?
And why hasn't everyone come around to the right answer like a million posts ago?
The right answer being that the plane does not take off.
Go back and read the whole thread. I challenge you, naysayers.
Max
And why hasn't everyone come around to the right answer like a million posts ago?
The right answer being that the plane does not take off.
Go back and read the whole thread. I challenge you, naysayers.
Max
Cal Weldon said:
Cal,
I got past that a few months ago when I last posted in this insane thread...........
The jets are not directly coupled to the wheels and as such, the plane must move forward (at least a tiny amount) for the wheels to turn at all. At the point that the plane has made forward progress and the wheels have started to turn, at some point the stipulations of the original question have been broken. But the pilot already knows that so he put the wheel brakes on before starting the jets.... The plane and the belt move forward accellerating until the plane takes off. The wheels remain stationary relative to a point on the belt.
Hi Max,
No political discussion. It was just a joke that needed to be clairified. 🙁
The correct answer was arrived at a million posts ago, we are just trying to help Cal understand it 😱 😀
I don't agree with you, but Cal likes you.
No need to read, we've been here all the time. 😎
And finally .... what ever Dan says - goes .
-Chris
No political discussion. It was just a joke that needed to be clairified. 🙁
The correct answer was arrived at a million posts ago, we are just trying to help Cal understand it 😱 😀
I don't agree with you, but Cal likes you.
No need to read, we've been here all the time. 😎
And finally .... what ever Dan says - goes .
-Chris
AudioFreak said:
quasi said:
That's it, you're all insane. I'm unsubscribing (again). Cal, I suggest you join me. It's hopeless here.
Max
Hi Max,
It's kind of funny when the other side says we are missing something, don't you think? They are still stuck in the thrust and decoupling of the wheels and wondering what happens to the thrust and are blissfully overlooking the most important part. I wish I were a better instructor. This really isn't that tough.
Al, The thrust is used up in the planes ATTEMPT to move forward creating the potential infinite wheel/belt speed. The greater the thrust, the greater speed at which the wheel approachs the infinite speed.
Dan, the actual speed created by the thrust and therefore starting the wheels in motion is an infintesimal amount. The belt moves at the same speed as the wheels, we are not to factor in drag or friction. This is not a real world situation.
I am going to try and put this into perspective so that we get past the thrust issue and try and show why the plane will not move regardless of thrust. I will return.
It's kind of funny when the other side says we are missing something, don't you think? They are still stuck in the thrust and decoupling of the wheels and wondering what happens to the thrust and are blissfully overlooking the most important part. I wish I were a better instructor. This really isn't that tough.
Al, The thrust is used up in the planes ATTEMPT to move forward creating the potential infinite wheel/belt speed. The greater the thrust, the greater speed at which the wheel approachs the infinite speed.
Dan, the actual speed created by the thrust and therefore starting the wheels in motion is an infintesimal amount. The belt moves at the same speed as the wheels, we are not to factor in drag or friction. This is not a real world situation.
I am going to try and put this into perspective so that we get past the thrust issue and try and show why the plane will not move regardless of thrust. I will return.
Hi Cal,
I'll quote the question for you ....
If we look at it a piece at a time, maybe it will help.
-Chris
I'll quote the question for you ....
I am unclear as to your interpretation, so break it down bit by bit so I can follow you. I accept that there are a number of ways you can interpret the question, so let's exclude things that violate the laws of physics completely. I'll accept technology beyond the current state of the art.
If we look at it a piece at a time, maybe it will help.
-Chris
Cal Weldon said:
I refer you back to my practical experiment, no matter how fast I pulled the paper out from under the roller, it always moved forward. I haven't noticed anyone else actually trying this experimentally, you're all happy just playing mind games!
😉
OK. I'm not banned yet so.... 😀
In order for the wheels to turn, the plane must move forwards. If the plane was prevented from moving forwards by the action of the belt, the wheels would never start turning so the belt would never move. The plane would just sit there roaring it's engines off by virtue of the fact it was sitting on a stationary conveyor belt.
I'm fairly sure this wouldn't actually be the case IRL. 🙂
In order for the wheels to turn, the plane must move forwards. If the plane was prevented from moving forwards by the action of the belt, the wheels would never start turning so the belt would never move. The plane would just sit there roaring it's engines off by virtue of the fact it was sitting on a stationary conveyor belt.
I'm fairly sure this wouldn't actually be the case IRL. 🙂
OK then I have to chip in.....Though I cant believe we are doing this all over again!
I believe the essense of enlightenment is to be able to see all perspectives and indeed there are only a few people here that do this.
Ask yourself a basic question.....
If the engines want to move then what's stopping them?
The wheels? No! because they are free to move.
The belt? No! because it is free to move also
Both together....now thats a different question but....
even if the belt and the wheels were locked then the force of the engines propulsion would easily overcome the frictional drag.............and the plane would haul it's *** down the runway leaving a large rubber line behind it!
The only question that you can then ask is......
Would the tyres explode.......then the undercarriage collapse....and therefore.......CRUNCH.
Sorry, but if we are to overlook the FLAWS of the question then......because nothing is locked and everything is free to move then the plane MUST take off....that's it...end of!
Unless you are one of the expodential thinkers who believe that the wheels explode due to excesive rotational speed etc etc etc....but again, this scenario is questionable against the lack of information in the question......
I'm off to dinner...redwine......ooooooooh!
I believe the essense of enlightenment is to be able to see all perspectives and indeed there are only a few people here that do this.
Ask yourself a basic question.....
If the engines want to move then what's stopping them?
The wheels? No! because they are free to move.
The belt? No! because it is free to move also
Both together....now thats a different question but....
even if the belt and the wheels were locked then the force of the engines propulsion would easily overcome the frictional drag.............and the plane would haul it's *** down the runway leaving a large rubber line behind it!
The only question that you can then ask is......
Would the tyres explode.......then the undercarriage collapse....and therefore.......CRUNCH.
Sorry, but if we are to overlook the FLAWS of the question then......because nothing is locked and everything is free to move then the plane MUST take off....that's it...end of!
Unless you are one of the expodential thinkers who believe that the wheels explode due to excesive rotational speed etc etc etc....but again, this scenario is questionable against the lack of information in the question......
I'm off to dinner...redwine......ooooooooh!
Cal Weldon said:
Ah yes but if the belt move back at the same speed as the wheels move forward (with no lag) then so long as you maintain that, the plane never gets moving.
More than that...
Once the wheels get moving (somehow) the plane must continue to make forward progress for the wheels to be able to gain speed. Again somehow the plane is getting ahead of the belt. As soon as the plane is kept "on the spot" (even once the wheels are moving) assuming the rest of the system is frictionless and the wheel mating with the belt is perfect (no skids allowed), then the small amount of friction in the wheel assembly and the weight of the plane bearing down upon the ground / belt will ensure that the wheels lose speed instead of gaining it.
According to the laws of physics, when the wheels start rotating forward, the belt must start moving backwards. Since the belt is moving in the opposite direction of rotation, it is moving forward, and not letting the wheels rotate. So the wheels do not rotate, and the belt moves forward with the plane. Plane takes off.
xplod1236 said:
Although you are correct about take-off, you need to draw the direction of movement on a piece of paper to see that opposing rotations actually move together.
You are right though....the plane don't care what the wheel s are doin'!
There is a post somewhere in the archives that shows it...somewhere....sometime....in the past!
This is the plane to settle many arguments.
http://www.militaryfactory.com/aircraft/detail.asp?aircraft_id=47
Doesn't care about wheels, conveyor belts, servo linked mechanisms or decoupled flaming axles.
Why am I still here .....sigh
http://www.militaryfactory.com/aircraft/detail.asp?aircraft_id=47
Doesn't care about wheels, conveyor belts, servo linked mechanisms or decoupled flaming axles.
Why am I still here .....sigh
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