Can the plane take off?

I hope everyone was able to get out on the water and enjoy the 4th.
Again, the replies do not follow the one rule applied by the word problem.
The wheels can not rotate faster than the surface they are touching. Not one of the examples used stays with in the proposed parameters. The physical characteristics of the plane, it's engines, the fact that the wheels are not driven are all irrelevant to the wording with in the problem. Give me one example where the plane can can take off without the wheel rotating faster than the conveyor violating the stated Implied rule.
Imagine a belt sander turned on it's back, your little hot wheels car sitting on it. Turn it on, it shoots off the back. Now hold it in place centered on the belt, turn it on it stays where you hold it, now move your hand in a forward direction to simulate more engine thrust, noting the wheels are not being driven by your hand(simulated thrust) but also notice that the wheels are rotating faster(against the implied rule of the problem). Stop explaining in the real world and adhere to the problem presented. In every example you present the wheels have to rotate faster than the surface it's in contact with which violates the implied rule.
 
R&A Nash said:
I hope everyone was able to get out on the water and enjoy the 4th.
Again, the replies do not follow the one rule applied by the word problem.
The wheels can not rotate faster than the surface they are touching. Not one of the examples used stays with in the proposed parameters. The physical characteristics of the plane, it's engines, the fact that the wheels are not driven are all irrelevant to the wording with in the problem. Give me one example where the plane can can take off without the wheel rotating faster than the conveyor violating the stated Implied rule.
Imagine a belt sander turned on it's back, your little hot wheels car sitting on it. Turn it on, it shoots off the back. Now hold it in place centered on the belt, turn it on it stays where you hold it, now move your hand in a forward direction to simulate more engine thrust, noting the wheels are not being driven by your hand(simulated thrust) but also notice that the wheels are rotating faster(against the implied rule of the problem). Stop explaining in the real world and adhere to the problem presented. In every example you present the wheels have to rotate faster than the surface it's in contact with which violates the implied rule.
Click to expand...
Read the parameters again - "the conveyor belt is designed to exactly match the speed of the wheels, moving in the opposite direction". Therefore, the conveyor belt is variable in speed dependent upon the wheel speed.
The correct answer is found by understanding the conveyor belt and aircraft wheels are separate and independent mechanisms from the mechanism moving the aircraft forward (jet engines).
index.php
 
Are you implying that the wheels speed is irrelevant to the aircrafts movement. Not possible. The main thing to overcome with flight here is gravity which in fixed wing craft requires ground speed to get air flow over the wings correct? Your implying that the plane is some how able to move on the conveyor with gravity in place wheel speed not exceeding the conveyor belt speed. In your scenario the plane would take off once the wheel speed reached approximately 180 mph faster than the conveyor belt was moving.
This violates the implied rule.
Unless this plane can levitate it can not move as long as the wheels and conveyor are matching speed in opposite directions.
If the point is to say that the plane will take off because the thrust will over power the speed of the conveyor at some point than yes, but only if the wheel speed exceeds the speed of the conveyor belt running in reverse. Is gravity keeping the plane in contact with the conveyor? Yes.
Is thrust causing wheel rotation? Yes. Is the conveyor belt cancelling forward motion by moving in the opposite direction at an identical speed? Yes.
Therefore no ground speed can be achieved without a levitating plane.
 
R&A Nash said:
I hope everyone was able to get out on the water and enjoy the 4th.
Again, the replies do not follow the one rule applied by the word problem.
The wheels can not rotate faster than the surface they are touching. Not one of the examples used stays with in the proposed parameters. The physical characteristics of the plane, it's engines, the fact that the wheels are not driven are all irrelevant to the wording with in the problem. Give me one example where the plane can can take off without the wheel rotating faster than the conveyor violating the stated Implied rule.
Imagine a belt sander turned on it's back, your little hot wheels car sitting on it. Turn it on, it shoots off the back. Now hold it in place centered on the belt, turn it on it stays where you hold it, now move your hand in a forward direction to simulate more engine thrust, noting the wheels are not being driven by your hand(simulated thrust) but also notice that the wheels are rotating faster(against the implied rule of the problem). Stop explaining in the real world and adhere to the problem presented. In every example you present the wheels have to rotate faster than the surface it's in contact with which violates the implied rule.
Click to expand...
You aren’t adhering to the problem when you create a scenario where the system doesn’t even work. The conveyor is designed to move at the same speed as the wheels. Therefore the wheels MUST move.
 
R&A Nash said:
Are you implying that the wheels speed is irrelevant to the aircrafts movement. Not possible. The main thing to overcome with flight here is gravity which in fixed wing craft requires ground speed to get air flow over the wings correct? Your implying that the plane is some how able to move on the conveyor with gravity in place wheel speed not exceeding the conveyor belt speed. In your scenario the plane would take off once the wheel speed reached approximately 180 mph faster than the conveyor belt was moving.
This violates the implied rule.
Unless this plane can levitate it can not move as long as the wheels and conveyor are matching speed in opposite directions.
If the point is to say that the plane will take off because the thrust will over power the speed of the conveyor at some point than yes, but only if the wheel speed exceeds the speed of the conveyor belt running in reverse. Is gravity keeping the plane in contact with the conveyor? Yes.
Is thrust causing wheel rotation? Yes. Is the conveyor belt cancelling forward motion by moving in the opposite direction at an identical speed? Yes.
Therefore no ground speed can be achieved without a levitating plane.
Click to expand...
You are still trying to tie wheel speed with aircraft speed….

The conveyor belt does NOT cancel forward motion. It just increases wheel speed. That is the only thing it does. Aircraft speed over ground is not affected by the belt.
 
R&A Nash said:
Are you implying that the wheels speed is irrelevant to the aircrafts movement. Not possible. The main thing to overcome with flight here is gravity which in fixed wing craft requires ground speed to get air flow over the wings correct? Your implying that the plane is some how able to move on the conveyor with gravity in place wheel speed not exceeding the conveyor belt speed. In your scenario the plane would take off once the wheel speed reached approximately 180 mph faster than the conveyor belt was moving.
This violates the implied rule.
Unless this plane can levitate it can not move as long as the wheels and conveyor are matching speed in opposite directions.
If the point is to say that the plane will take off because the thrust will over power the speed of the conveyor at some point than yes, but only if the wheel speed exceeds the speed of the conveyor belt running in reverse. Is gravity keeping the plane in contact with the conveyor? Yes.
Is thrust causing wheel rotation? Yes. Is the conveyor belt cancelling forward motion by moving in the opposite direction at an identical speed? Yes.
Therefore no ground speed can be achieved without a levitating plane.
Click to expand...
Now an "implied rule"??
The wheels and conveyor have nothing to do at all with the movement of the aircraft other than the wheels may or may not be rotating. The conveyor simply matches the wheel speed but in the opposite direction (this is the rule). If you had a string attached to the aircraft and was pulling it forward there is nothing the conveyor can do to stop the forward movement unless, of course, you applied the wheel brakes. The aircraft engines are no different than pulling on the string. Again, they are separate and independent mechanisms.
 
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R&A Nash said:
Are you implying that the wheels speed is irrelevant to the aircrafts movement. Not possible. The main thing to overcome with flight here is gravity which in fixed wing craft requires ground speed to get air flow over the wings correct? Your implying that the plane is some how able to move on the conveyor with gravity in place wheel speed not exceeding the conveyor belt speed. In your scenario the plane would take off once the wheel speed reached approximately 180 mph faster than the conveyor belt was moving.
This violates the implied rule.
Unless this plane can levitate it can not move as long as the wheels and conveyor are matching speed in opposite directions.
If the point is to say that the plane will take off because the thrust will over power the speed of the conveyor at some point than yes, but only if the wheel speed exceeds the speed of the conveyor belt running in reverse. Is gravity keeping the plane in contact with the conveyor? Yes.
Is thrust causing wheel rotation? Yes. Is the conveyor belt cancelling forward motion by moving in the opposite direction at an identical speed? Yes.
Therefore no ground speed can be achieved without a levitating plane.
Click to expand...
jmauld said:
You are still trying to tie wheel speed with aircraft speed….

The conveyor belt does NOT cancel forward motion. It just increases wheel speed. That is the only thing it does. Aircraft speed over ground is not affected by the belt.
Click to expand...
ttmott said:
Now an "implied rule"??
The wheels and conveyor have nothing to do at all with the movement of the aircraft other than the wheels may or may not be rotating. The conveyor simply matches the wheel speed but in the opposite direction (this is the rule). If you had a string attached to the aircraft and was pulling it forward there is nothing the conveyor can do to stop the forward movement unless, of course, you applied the wheel brakes. The aircraft engines are no different than pulling on the string. Again, they are separate and independent mechanisms.
Click to expand...
Thanks guys, but they must have had @R&A Nash in mind when they wrote this.
"Some men you just can't reach"
 
It's just sad that this thread wasn't able to compete with the bikini thread in terms of volume. I thought we had a shot at it initially.

Birds don't have wheels? Or....do they? :)

upload_2022-7-6_9-58-36.png
 
Stee6043 said:
It's just sad that this thread wasn't able to compete with the bikini thread in terms of volume. I thought we had a shot at it initially.

Birds don't have wheels? Or....do they? :)

View attachment 130010
Click to expand...
It's all about the logic division between artists/accountants/psychiatrists/attorneys and engineers/scientists/designers/mechanics.
 
I believe I have I've seen the error in my thoughts and stand corrected. I was hung up on the wheel touching the ground as some of you have explained. Over and out.
 
Well, how embarrassing. I took a day to get out from under my rock and read some of the posts I made. Man I was really hung up on those wheels turning. What's sad is I know better or did at one time. I spent 10 years back in the 70's and 80's working on the flight controls and landing gear of F-4's and F-16's. So thanks for the post about the rope pulling the plane that was the one that snapped me out of my fixation. I just kept seeing that plane with the conveyor moving the plane backwards and applying thrust and it keeping the plane from moving. Couldn't get passed that for awhile. To those who choose to belittle or insult, well I imagine that is something you need to do to feel good. I guess now that I think about it that is probably more of an embarrassment than me running with the wrong thoughts on the proposed scenario. Hopefully most will find this if nothing else as entertaining.
 
Glad you got it worked out, and have converted to the dark side. Now you get to help us defend the solution when the next guy pops in.

FWIW, I thought your first post in here was a troll post.
 
R&A Nash said:
Well, how embarrassing. I took a day to get out from under my rock and read some of the posts I made. Man I was really hung up on those wheels turning. What's sad is I know better or did at one time. I spent 10 years back in the 70's and 80's working on the flight controls and landing gear of F-4's and F-16's. So thanks for the post about the rope pulling the plane that was the one that snapped me out of my fixation. I just kept seeing that plane with the conveyor moving the plane backwards and applying thrust and it keeping the plane from moving. Couldn't get passed that for awhile. To those who choose to belittle or insult, well I imagine that is something you need to do to feel good. I guess now that I think about it that is probably more of an embarrassment than me running with the wrong thoughts on the proposed scenario. Hopefully most will find this if nothing else as entertaining.
Click to expand...
All good man.
 
jmauld said:
They would not need to produce double thrust. Normal thrust will do the job.
Click to expand...
But eventually the drag of the tires would force it back at the speed of the “treadmill” therefore it would be traveling in reverse at takeoff speed. Normal
Thrust would get it back to a standstill... I think. NEVERMIND ha my head hurts now.
 
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