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%
Voters: 74. You may not vote on this poll
will the plane fly?
Registered User
Joined: Apr 2005
Posts: 1,222
Likes: 69
From: Old Norte Mexico
Originally Posted by gman07
The plane will never move. In order for it to accelerate relative to the ground (and therefore the air around it), the wheels must turn faster than the conveyor belt.
The thrust of the engine is "thrusting" the plane ahead regardless of what the ground (or conveyor belt) is doing. The speed of the plane is independent of the ground's speed. If the plane was dependent on what the ground was doing in order to move, it would be called a bus/truck/car.
Oh, and yeah, the bottom of the tread on a tank is going 0 MPH, just like the bottom of the tire on your truck (unless you are smokin em).
Registered User
Joined: May 2005
Posts: 1,060
Likes: 1
From: Peoria, IL
Originally Posted by FMB
How do you think a plane gains speed if it were on skiis on a frozen lake? No wheels to turn. The speed of the plane is not tied to the speed of the wheels
Originally Posted by FMB
The thrust of the engine is "thrusting" the plane ahead regardless of what the ground (or conveyor belt) is doing. The speed of the plane is independent of the ground's speed.
Registered User
Joined: Sep 2005
Posts: 49
Likes: 0
From: Western n.c
Originally Posted by Begle1
The wheels on the airplane eliminate friction between the ground and the craft.
As the airplane's jet engines create thrust, the airplane will move forward. The wheels are attached to the airplane, so the wheels as well will move forward. The airplane doesn't have to overcome the conveyer belt.
The point of the puzzle is that despite the conveyer belt, the plane will move forward. While a stationary plane will not take off, there is no way the conveyer will hold the plane stationary. So the plane will take off, provided that it can overcome the axle's friction, which shouldn't be factored into the equation.
Swimming upstream in a river would be like the airplane taking off in a very strong headwind. A better analogy would be to strap a rocket on your back, put on roller skates, and then get on a tread mill... No matter how fast the treadmill is moving backwards, the rocket will move forwards because the rollor blades remove the friction between you and the belt.
Another analogy would be to take a rolling pin and hold it on a conveyor belt. You can turn the conveyor belt on as fast as you want, but no matter how fast it is moving you can always roll the rolling pin forward on the conveyer belt with the same amount of force. The only difference is that the pin will be rotating faster as the belt moves faster, but the same amount of "thrust" will always move the pin forward the same distance.
I was initially wrong because I was thinking that the airplane's engines were moving the jet's wheels, which is obviously wrong.
As the airplane's jet engines create thrust, the airplane will move forward. The wheels are attached to the airplane, so the wheels as well will move forward. The airplane doesn't have to overcome the conveyer belt.
The point of the puzzle is that despite the conveyer belt, the plane will move forward. While a stationary plane will not take off, there is no way the conveyer will hold the plane stationary. So the plane will take off, provided that it can overcome the axle's friction, which shouldn't be factored into the equation.
Swimming upstream in a river would be like the airplane taking off in a very strong headwind. A better analogy would be to strap a rocket on your back, put on roller skates, and then get on a tread mill... No matter how fast the treadmill is moving backwards, the rocket will move forwards because the rollor blades remove the friction between you and the belt.
Another analogy would be to take a rolling pin and hold it on a conveyor belt. You can turn the conveyor belt on as fast as you want, but no matter how fast it is moving you can always roll the rolling pin forward on the conveyer belt with the same amount of force. The only difference is that the pin will be rotating faster as the belt moves faster, but the same amount of "thrust" will always move the pin forward the same distance.
I was initially wrong because I was thinking that the airplane's engines were moving the jet's wheels, which is obviously wrong.
Registered User
Joined: May 2005
Posts: 1,060
Likes: 1
From: Peoria, IL
Originally Posted by Hoss
I won't mention any names, but there are some ignorant people on this board. 
If you think the plane WON'T take off, then you just might be one of them.
If you think the plane WON'T take off, then you just might be one of them.
So is there an official answer to this thing?
Registered User
Joined: Sep 2005
Posts: 49
Likes: 0
From: Western n.c
Originally Posted by Geico266
Beam, at least the "rocket scientists" who responded before you could read. 
There is no need for derogitory remarks towards others, all that does is stiffle creative thought. This is a thinking person's thread.
Rammtuff said it best..... we need more beer.
There is no need for derogitory remarks towards others, all that does is stiffle creative thought. This is a thinking person's thread.Rammtuff said it best..... we need more beer.
Thats MR Hoss to you buddy!
Joined: Jul 2001
Posts: 2,759
Likes: 3
From: Central Texas
What some of you folks are failing to realize is that even though the wheels of the plane are not what makes it move, if the conveyor belt is always pushing back with the same force that the thrust of the engines is pushing forward then simple physics tells us that the plane can NOT move.
Come on now...use that ole' brain the good Lord gave you.
By the way, Beamwalker, I am a genius so I didn't take offense to the "rocket scientist" comment.
Come on now...use that ole' brain the good Lord gave you.
By the way, Beamwalker, I am a genius so I didn't take offense to the "rocket scientist" comment.
Registered User
Joined: Apr 2005
Posts: 1,222
Likes: 69
From: Old Norte Mexico
Originally Posted by gman07
As long as the wheels are pressed to the ground with a force (equal to the weight of the plane by Newton's third law) there is friction between the wheels and the ground. This is why when a plane is taking off the wheels turn. The speed the wheels turn at is directly proportional to the speed of the plane.
Originally Posted by gman07
The engine is producing thrust, which will tend to make it accelerate.
Originally Posted by gman07
However, for the plane to move relative to the ground, the wheels must turn faster than the conveyor belt.
Originally Posted by gman07
If the wheels are moving at the same speed, the vehicle goes nowhere, whether it is jet powered or the wheels are driven. The conveyor belt will accelerate almost infinitely fast (which would be impossible if we were not talking about this theoretically) until a point is reached at which the rolling resistance is equal to thrust.
Now, a different question..... what if the plane powers up to take off but leaves the parking brake on? Will the conveyor belt have any affect?
Of course it will. If the conveyor belt moves ahead, so will the plane. If the conveyor belt moves to the rear, so will the plane. If the conveyor belt moves not at all, so will the plane.
Thats MR Hoss to you buddy!
Joined: Jul 2001
Posts: 2,759
Likes: 3
From: Central Texas
Here's a question for you guys about the dozer. If the levers that control the dozer tracks are pushed forward and backwards so that the dozer is rotating counter clockwise at a rate of 2,160 degrees per minute, how fast are the tracks moving on top and bottom and how long will it take before the operator gets dizzy??
Registered User
Joined: Jul 2004
Posts: 1,252
Likes: 52
From: Whitehorse, cultural hub of the universe..
Having been there in a mini excavator, that is only 6rpm. chances of getting dizzy are close to nil. However, if you could get a dozer to spin that fast, the tracks would still not be moving.
Wonderful stuff.
Wonderful stuff.
Registered User
Joined: May 2005
Posts: 1,060
Likes: 1
From: Peoria, IL
Originally Posted by FMB
Ummmm.... so then when the plane is about to land and the wheels are turnign at 0 MPH, the speed of the plane must therefore also be equal to 0 MPH? This is gettin good. Actually, the wheel spin is directly proportional to the speed of the solid surface it is rolling on which does not necessesarily corrolate with the ground speed.
Originally Posted by FMB
You are still stuck on the theory that a plane must have wheels? And that they must turn faster than the surface it is rolling on? In other words, it must be "Peeling out"? How does that happen on a conveyor belt?
Originally Posted by FMB
The conveyor belt is not pushing the plane backwards, it is just spinning the wheels.
Im going to bed now, I'll be back in the morning to continue the debate
