Skill's weekend teaser

[raysor]

Ok a bad example maybe. My bad. Raysor - what drag are you talking about? And a 747 does have wing you pleb!

Are you blind as well as thick? Read the post before acting like a prat.

 

[TheBramble]

These people went quiet once it was pointed out that actually, the jet engines create there own drive and push the air backwards and the plane forward. The wheels just spin freely on there axels.

They probably went quiet out of respect for the death of intelligence they had just witnessed.

Yes, the jet engines DO ‘create their own drive’ and they DO push the air backwards and therefore the plane forwards. And yes, the wheels DO just spin freely on their axes. All of this is true and all has been agreed by both the Flat-Earthers and by those of us who got the teaser correct.

What happens when the plane starts to move forward? What is the conveyor belt doing? What is the net result of these two actions?

 

[raysor]

They probably went quiet out of respect for the death of intelligence they had just witnessed.

Yes, the jet engines DO ‘create their own drive’ and they DO push the air backwards and therefore the plane forwards. And yes, the wheels DO just spin freely on their axes. All of this is true and all has been agreed by both the Flat-Earthers and by those of us who got the teaser correct.

What happens when the plane starts to move forward? What is the conveyor belt doing? What is the net result of these two actions?

I was just thinking about that bit. If the plane 'moves' forward then at some point, if the forward movement creates air-flow, the plane will take off.

 

[TheBramble]

but when the jetwash hits him, will he stay on the conveyor belt going round and round swearing at skill ?

Not at all Claudia. I am a gentleman.

Each time the conveyor brought me round to Skill's window on the plane (which remains quite stationary relative to a fixed external reference point) as he waits patiently (but pointlessly) at the end of the runway with the engines still blowing full, I'd give him a cheery wave and hold up my (increasingly blackened) placard on which will be written "+X-X=0".

 

[TheBramble]

I was just thinking about that bit. If the plane 'moves' forward then at some point, if the forward movement creates air-flow, the plane will take off.

Yes, it would. But we are told by Skills that the movement of the wheels of the plane are exactly matched by an opposite and equal movement in the conveyor. So it can never move forward.

As soon as the wheels even suggest a mere intention to creep an iota of hint of a fraction of an atom's radius, the conveyor is already doing the same.

 

[MrGecko]

They probably went quiet out of respect for the death of intelligence they had just witnessed.

Yes, the jet engines DO ‘create their own drive’ and they DO push the air backwards and therefore the plane forwards. And yes, the wheels DO just spin freely on their axes. All of this is true and all has been agreed by both the Flat-Earthers and by those of us who got the teaser correct.

What happens when the plane starts to move forward? What is the conveyor belt doing? What is the net result of these two actions?

The conveyor belt moving of its own accord does not move the plane, it just makes the wheels go around. Once the plane starts to produce thrust, it will have a force causing it to move in the fixed reference frame - in order for it to remain stationary, there must be another force acting directly on the plane;

Using the translational / angular terminilogy, a translational displacement of plane the cannot be opposed by the conveyor; the conveyor adds angluar velocity to the wheels, not translational velocity to the plane.

Imagine the plane and the conveyor are stood still, no engines, no friction... if the conveyor starts to move, the plane stays exactly where it is, its the wheels that spin around.

 

[Hotch]

Rep for avatar Gecko, legendary.

Edit....

The problem is discovered! (maybe I'm slow on the uptake). I thought this was discussed ages back, but seemingly not.

Bramble's problem (might be) is that the question is worded perfectly, the conveyor belt should move at the speed of the plane. As mentioned in a few posts by me, the wheels will be spinning twice as fast as with a normal take off (ish)

Also, bramble and skill both have a severe bout of USD (uber stubbornness disorder) .

 

[TheBramble]

So Bramble your view is that "the speed of the planes wheels" refers to translational velocity of, say, the wheels axle, as viewed by someone standing in the fixed reference frame

while

"the speed of the planes wheels" refers, in another case, to the speed at which the wheels are rotating around their axle, remaining stationary (bar the spinning) to the same viewer in the fixed reference frame.

Basically, translational vs. rotational kinetic energy.

??

Gecko, your problem if I may be so bold, is that you're too intelligent. You're looking I suspect for scientifically, mathematically, physically correct answers. You’re basically reading too much into the question and tripping up on what is after all, a teaser, it’s supposed to trip the bright, clever, gifted ones up. That’s the whole point. They and you all go off with your perfectly correct and rigorously researched responses, and completely miss the point. Which of course, is the entire point. Dullards and dorks like me see it straight away. The benefits of a poor education and (delightfully) misspent youth.

Speed and energy don’t come into this – rotational, lateral, translational, kinetic…red herrings.

The rotation of the wheel WILL translate into linear movement of the wheel along the surface upon which it is located. It’s just that in this case, the surface upon which it is located will have moved an equal distance in the opposite direction at the same time. The wheels will have rotated. The axes however will not have moved one iota.

 

[raysor]

The conveyor belt moving of its own accord does not move the plane, it just makes the wheels go around. Once the plane starts to produce thrust, it will have a force causing it to move in the fixed reference frame - in order for it to remain stationary, there must be another force acting directly on the plane;

Using the translational / angular terminilogy, a translational displacement of plane the cannot be opposed by the conveyor; the conveyor adds angluar velocity to the wheels, not translational velocity to the plane.

Imagine the plane and the conveyor are stood still, no engines, no friction... if the conveyor starts to move, the plane stays exactly where it is, its the wheels that spin around.

You haven't answered anything here! We know that the thrust pushes the plane forwards, due to where there's a force there will be an opposing one. The next thing you need to take off is lift. This is obtained by airflow over the wing. The airflow over the conveyor belt is nil. Therefore the plane must move forward relative to the conveyor belt. Can this happen with the set up as posed by the original puzzle?
I am not attempting to think about that bit at the moment!

 

[wasp]

Rep for avatar Gecko, legendary.

Reps for everyone for the perseverance to still be going on about this ****1ing plane!

 

[raysor]

You haven't answered anything here! We know that the thrust pushes the plane forwards, due to where there's a force there will be an opposing one. The next thing you need to take off is lift. This is obtained by airflow over the wing. The airflow over the conveyor belt is nil. Therefore the plane must move forward relative to the conveyor belt. Can this happen with the set up as posed by the original puzzle?
I am not attempting to think about that bit at the moment!

Ah, yes! The forward force (created by the jet thrust) is transferred through the axles and to the wheels and then to the conveyor belt. Bit like Newton's cradle. All that energy from the moving ball is transferred to the next ball and then back again.

 

[TheBramble]

The conveyor belt moving of its own accord does not move the plane, it just makes the wheels go around.

No. The conveyor belt does NOT make the wheels go round. The conveyor responds instantly and mystically (Skills has never disclosed how it does this, but we are told it does, so it is a given) to the first slight intent of any movement by the wheels and responds with an equal and opposite movement.

Once the plane starts to produce thrust, it will have a force causing it to move in the fixed reference frame - in order for it to remain stationary, there must be another force acting directly on the plane;

There you go again. You’re thinking literally –as if in real life. Yes, it will produce a thrust that will cause it to move relative to a fixed external reference point. No other force acts on the plane to cause it to remain stationary. The plane is moving – relative to the conveyor belt.

Using the translational / angular terminilogy, a translational displacement of plane the cannot be opposed by the conveyor; the conveyor adds angluar velocity to the wheels, not translational velocity to the plane.

Nothing is opposing the plane. The plane is doing exactly what is should do and what it always does.

Imagine the plane and the conveyor are stood still, no engines, no friction... if the conveyor starts to move, the plane stays exactly where it is, its the wheels that spin around.

Why would I want to do that? It has nothing to do with the teaser. In any event, (probably going to regret this) if you did carry out this manoeuvre, the plane would actually move with the conveyor (inertia).

 

[Hotch]

Once more, with feeling!

1-The question is worded poorly, I thought it was amended but maybe not. The conveyor matches the speed of the plane.

2-The plane moves forward.

3-At the end of the conveyor belt, the wheels are spinning twice as fast as they normally would on take off.

4-The plane takes off.

5-PANCAKES

 

[TheBramble]

1-The conveyor matches the speed of the plane.

2-The plane moves forward.

Did writing those two points one after the other not cause you even a moment's hesitation?

Unbelievable.

 

[raysor]

Did writing those two points one after the other not cause you even a moment's hesitation?

Unbelievable.

The only thing that worries me is how the forward energy is 'dissipated' through the axles and then to the rotational aspect of the wheels (especially without the aid of friction). Although the movement of the conveyor belt is in the same plane as the plane. i.e. the energy in the plane is going horizontally forward and the it is counteracted by the horizontal belt going the other way.
Do the stationarys have it?

 

[Hotch]

Did writing those two points one after the other not cause you even a moment's hesitation?

Unbelievable.

/give up

 

[raysor]

The only thing that worries me is how the forward energy is 'dissipated' through the axles and then to the rotational aspect of the wheels (especially without the aid of friction). Although the movement of the conveyor belt is in the same plane as the plane. i.e. the energy in the plane is going horizontally forward and the it is counteracted by the horizontal belt going the other way.
Do the stationarys have it?

In fact is it a bit of a red herring to single out the fact that it is a jet propelled plane?
After all a petrol engine would still be trying to exert thrust, even though it may be going diretly to the wheels (as in a car).
All the time the wheels are on the belt and going at the same speed, is it not irrelevant about where the power is coming from?

 

[raysor]

In fact is it a bit of a red herring to single out the fact that it is a jet propelled plane?
After all a petrol engine would still be trying to exert thrust, even though it may be going diretly to the wheels (as in a car).
All the time the wheels are on the belt and going at the same speed, is it not irrelevant about where the power is coming from?

Another thought. If the jet were on the tarmac and the wheel brakes were on (super brakes), the thrust from the jet wouldn't move the plane forward. Therefore there must be a connection between the jet's thrust, the wheels and the conveyor belt.Sorry MrGecko, your flight is cancelled, how about a nice boat trip?

 

[MrGecko]

err... hang on....

Bramble, the problem as described by Skill is on the Right, and we are all on the left?

Is that your position?

EDIT:

Err... well, yes, I am a gnats c0ck away from changing my mind and saying the plane DOESN'T take off. If you did it in real life, the plane would take off - but Skill has described a situation that could never exist in real life - Using the rollers in the diagram attached, we are (were) all thinking that the conveyor belt works like the one on the left (as it would in real life) - yet, look at the translational displacement of the dot, and it's "mirror" (the square) on the lower roller... THE DISPLACEMENT IS THE SAME

The problem initially stated that the displacement would be OPPOSITE, which is what we have on the right... -2r + 2r = 0.

Bramble, can you confirm?

 

[raysor]

err... hang on....

Bramble, the problem as described by Skill is on the Right, and we are all on the left?

Is that your position?

Put it this way. You have a box on wheels on a conveyor belt. You push the box with your finger and at the same time someone winds the belt in the opposite direction. What happens? Ah, you ask where does the thrust from my finger go?
And for the idiot who called me a pleb, we can put some wings on the box if you like! LOL