logic question

yeh thats the thing stopping me from saying yes... all the points rik says above are 100% correct...

but if the conveyer matches any rotation of the wheel in >>> direction equally by moving at <<<

then when the jets are activated giving prepoulsion adding >>>>>> then the conveyer must by logic meet this by adding <<<<<< in the other....

well who cares Rik lets get a toy(?) got to asda checkouts to test it lol...
 
actually you could very simply. A balloon glued to a chasis with wheels would test it... Anyone got a treadmill?
 
Whay see i'm right :D :D :D go me :)

for the plane to move forwards it only has to overcome air resistance not friction all the convayor belt does is increase the speed of the wheels but that doesn't slow the plane down.

if it was a car then the car would stay still but because its powered by a jet engine then it can push forward off the air.

its hard to explain...

oh and BTW the wheels on the plane would be turning the same way as they normally do. for them to go backwards the belt would have to work in the plane's favour...
 
think about it this way... imagine a shopping trolly on a conveyer belt that moving 10000000000million miles an hour.. because the wheels free move... the trolly remains stationary... if you sellotaped a rocket to it... it would move...

if you put a sail on it.. +bit of wind .......it would move..

Infact.. a strong wind... it would move... the wheels are completly INDEPENDANT from the trolly...

In this case being a plane... That was very good RIK... it fools us because of the way its been cleverly worded...
 
mean micra said:
yeh thats the thing stopping me from saying yes... all the points rik says above are 100% correct...

but if the conveyer matches any rotation of the wheel in >>> direction equally by moving at <<<

then when the jets are activated giving prepoulsion adding >>>>>> then the conveyer must by logic meet this by adding <<<<<< in the other....

well who cares Rik lets get a toy(?) got to asda checkouts to test it lol...

i see what you mean but all that would happen is that the belt would try to move backwards as fast as the plane but it couldn't because the plane is still moving forward so the belt would get faster and faster to infinity but that wouldn't effect the plane.


its easier to imagine that the plane is already in the air and has no wheels
 
nah in reality the trolley would move because of the weight creating friction, but i see where you are going with it.
 
As im not gonna start thinking about the treadmill vs the jet engine i cant totally comment..lol

but theres nothing stopping a smaller version of this theory being tested with a treadmill and a model aircraft...anyone got these ? :)

also :

nizzanz1 said:
the egg. the 1st chicken would have come from this egg. the birds that mated to make this egg were not chickens, but something very similar but not quite chicken.

This isnt strictly true as the chicken in this case may have previously been born live, but as a result of them being eaten by predators the evolution of that species could have resulted in the switch to egg based. This would allow the individual to be protected until it arrived at a time it was more readily able to protect itself. :)
 
i know this but you need to overcome somay other factors to actually take off...

i agree with the points for it as they are all correct for overcoming friction but, none of these have taken into consideration that without the MOMENTUM created by the MASS of the plane ACCELERATING down the runway and then and only the extending the flaps to create lift due to air resistance...

tbh i think its one of them in THEORY it will work things.. but think how powerful those jets would have to be to move a mass like a plane under those circumstances, and imagine the whiplash passengers would have...

i adamently say NO

but for the benefit of the thread YEAH, BUT NO, BUT YEAH... no no no no no YES
 
Think, if you ran on a conveyor that free moved, you wouldn't move the conveyor would spin, this is like driving with the wheels. Now....

If somebody pushed you, then you would move down the conveyor



And with the chicken and egg, there's no argument, the egg came first. The chicken is an evolved species belonging to the same line as the velociraptor. Now, animals such as crocodiles have eggs! So eggs came first as they've been around since the dinosaurs, the chicken evolved much later. The accurate question should be..... What came first? The chicken on the CHICKEN EGG?

Now that also has an in-accuracy, as evolution is a slow process so the first chicken must have evolved from an egg that wasn't from a chicken. The real question is, when did the chicken become a chicken?
 
ok aside from mork and mindy :D nanoo nanoo btw.

The egg had to be grown, it cant just roll out from a puddle, then out pops a chicken....unless the puddle is like one of those egg dispensers you get in the shops, thats got a troll inside or somthing...hmmm. But that would mean the egg was from china....so the chinese. :D
 
this thread is funny as hell..its made me laugh so much how people dont change their mind and some do.

i said no it cant first of all...but then changed my mind when hearing the reasons why it could
 
right people arnt getting this. whatever the acceleration of the plane if the conveyer matches it, which in the first thread he said it can the plane will not move. no matter how fast the plane goes forward if the conveyor can match it goin the other way the plane will not move. i thought this was all theretical anyways coz there is no way that conveyer belt could accelerate the opposite was as fast as a plane could aclerate forward.
 
Okay well in in reality this would never work if it were to be tested as:

1) we don't have a conveyer belt runway :p
2) the conveyer belt would not be quick enough to match every single speed increase the plane's wheels would make (basically the plane would always be one step ahead of the converyer belt's speed - ever tried running on those funky fast walk things at the airport? Same thing there, you'll always have the upper hand on the machine as it will never be able to react to your speed changes like you can. The question requires us to think outside the square if you will - and humans aren't always too crash hot at thinking and working with situations which can never exist...)
3) the bearings in the aircraft's wheels would most likely melt before the plane got up enough airspeed to generate lift

Thats just in REALITY.

IF we move into THEORY in a perfect world....

Well to be frank I havent figured out the answer myself. On one hand I know that the aircraft's engines work seperately to the wheels (planes don't even need wheels, they put sleds on them in some countries!!) and that in theory an aircraft would be able to accelerate in air AND ground speed independantly to the wheels. Meaning that if we did not have mechanical limitations in the landing gear and conveyer belt runway, yes there is no reason why the aircraft cannot take off.

But like I said, I'm hardly qualified in the area.
 
yeah but wat im saying is that the engines are connected to the wheels albeit in a roundabout way. The engines turbines are connected to the planes, the plane is connected to the wheels. therefore the engines are connected to the wheels. As long as there is mass over the planes wheels they will be turning as the plane is accelerating forward. how can the plane accelerate independantly to the wheels if the wheels are still on the ground.
 
59 bhp is more than enough said:
im still adament that it wont, how can the plane travel along the cnveyor belt if the belt matches the speed of the wheels. the speed the wheels are turning is directly proportionate to the speed the plane is traveling. for example if the plane accelerates becuase of the thrust of the engine, the friction between the road and the rubber on the wheels would turn the wheels. if the conveyor belt matches the speed of the wheels then it will in turn match the speed of the plane if they are both proportionate. therefore the plane cannot travel forward and cannot get any wind resistance. i KNOW that the plane will not take off.


WRONG DUDE the wheels would just turn twice as fast the wheels have nothing to do with the planes forward movment there simply there to keep the body off the ground there not driven wheels

pick up a skate borad a roller skate or similar.. your arm is the thrust of the enginges the skate is the plane with tis free spinning wheels push it along the ground it moves, push it along a conveyorbelt it still moves forward the wheels just turn faster!!! you wouldnt sudenly be not able to push the bloody skatebord because its on a conveyer belt!!!
 
yeah but what im saying is if the conveyor senses the speed of the plane then whatever speed you push it along the conveyor belt will equalize the speed but in the opposite direction so how can the plane speed up if the conveyor belt keeps up with the speed of the plane but in the opposite direction? obviously this is all theoretical coz the conveyer would have to be an instantanious acceleration but in theory there is no way it would take off.
 
Umm, doesnt this all depend on the plane and ambient windspeed? For example a VTOL plane, e.g. Harrier Jump Jet would obviously be able to take off - its forward momentum has nothing to do with its ability to get airbourne.

And a light plane driving into a strong headwind only needs to generate enough lift to get airbourne and enough thrust to provide power, so you could do it if you got the engine rpm's up high enough to provide thrust and the windspeed provided enough lift...

Rob.
 
why are people side-tracking with VTOL and "this couldnt happen" its a theoretical question... anyway, someone with a treadmill needs to make a balloon powered chaisis and try it out :)
 
59 bhp is more than enough said:
yeah but what im saying is if the conveyor senses the speed of the plane then whatever speed you push it along the conveyor belt will equalize the speed but in the opposite direction so how can the plane speed up if the conveyor belt keeps up with the speed of the plane but in the opposite direction? obviously this is all theoretical coz the conveyer would have to be an instantanious acceleration but in theory there is no way it would take off.

Imagine that the plane is not on the conveyor, the conveyor tries to match the speed of the plane but it can't because the plane will always go faster. the conveyer will speed up exponentially to infinity but it doesn't act on the plane so the plane can still move forwards

your still thinking like the conveyor would push the plane backwards and act against it but it doesn't because the plane just rolls over the conveyor...

another way of looking at it is:

the conveyor moves in the opposite direction to the plane at the exact same speed that the plane moves...

so if the plane is not moving then neither is the conveyor as the plane moves forwards at say 3 mph the conveyor will move at 3 mph

so if the plane has reached the speed it has to to leave the ground the conveyor will be doing the same in the opposite direction.

nothing is stopping the plane from moving forward the conveyor is just rolling backwards so the wheels are spinning exactly 2 times faster than normal but other than that the plane takes off as normal :D

i can't explain it any better than that without puppets :p
 
raceowrx explanaiton of putting a skateboard on a conveyor belt has made me understand how the plane will take off. imagine your at tesco standing next to the checkout conveyor belt and for some reason the belt is going a 500mph. you can rest the skateboard pointing inthe opposite direction and keep it still with just you little finger holding it, even though the belt is traveling at 500mph. then all you have to do is it give a gentle push on the board and you have moved it in the opposite direction, EVEN though the belt is going 500mph in the opposite direction. if the checkout belt was really long, you could start walking next to it still pushing the skate board at walking pace, then you could run etc. the skateboard would get faster in the direction your pushing it.
 
nizzanz1 said:
raceowrx explanaiton of putting a skateboard on a conveyor belt has made me understand how the plane will take off. imagine your at tesco standing next to the checkout conveyor belt and for some reason the belt is going a 500mph. you can rest the skateboard pointing inthe opposite direction and keep it still with just you little finger holding it, even though the belt is traveling at 500mph. then all you have to do is it give a gentle push on the board and you have moved it in the opposite direction, EVEN though the belt is going 500mph in the opposite direction. if the checkout belt was really long, you could start walking next to it still pushing the skate board at walking pace, then you could run etc. the skateboard would get faster in the direction your pushing it.

it's simmilar to that other logical question:

if they make a fighter jet that can go faster than a speeding bullet (which they do) then if it fires a bullet from its machine guns won't the plane fly into the bullet and blow itself up?

answer is no because the bullet is already going faster than a speeding bullet because its on board the plane so it would go at faster than a speeding bullet plus the speed of a bullet as it is fired.

the skateboard is doing 500mph plus the speed you push it but you only need to push it as fast as you want to move it if that makes sense.
 
skateboard is doing 0mph plus the speed you push it. the wheels are doing 500mph + the speed you push it.
 
nizzanz1 said:
skateboard is doing 0mph plus the speed you push it. the wheels are doing 500mph + the speed you push it.

sorry yea thats what i ment :)
 
I still think it wouldn't take off.

152744706ead473e0.JPG


Reason why, in picture 1, then plane is not moving, therefore the conveyor belt is not turning. Picture 2 is an example of what people have been saying about rollerblades and conveyor belts/treadmills. Yes the belt and wheels are moving, shown by Vc and V respectively, but there is still a force being applied to the object (f) to stop it from moving backwards with the belt.

In picture 3, the engines are now providing a force (F) to attempt to move the plane forward. However, as the power the engine produces would be proportional to the speed the wheels turn at, the belt will just speed up also, so the plane will not move.

In other words, the throttle would be at 50%, the plane is travelling wheels are travelling at say 100mph, the belt is then going to travel at 100mph in the opposite direction. The the power is increased to 100%, then plane now travels at 200mph, but the belt then increases to 200mph.

Or to make it more interesting, it all depends on the maximum speed of what the belt can rotate at as the plane is going to have a maximum velocity :p
 
you're falling off a cliff on a boulder (think Whylee Cyote) a5 40mph, someone once said to me that before you hit the floor you can jump off and survive but you'd be travel at 4-mph still
 
is this the same as jumping in the air just before a falling lift hits the ground to stop the impact.

In zero gravity would you be able to put both feet in a bag and pick yourself up ?
 
the plane will take off.
some lucky parachutists have survived an impact of nearly 150mph when their parachute didnt open, they ,ust have hada asoft landing and not actually impact at 150mph though..
but 40mph could kill you. how fast is a jump? 10mph? could take that off the 40mph to give you 30mph impact, which could still kill you or break some bones.
 
nex i think youve explained why the plane would take off the best. im still pretty sure it wouldnt as there is arguments for both of them. but there is still the point off if both plane and conveyer are travelling at speed and the plane try to accelerate using the engines, wont that in turn rotate the wheels as the plane is still on the ground. the conveyer would then sense this and speed up.
 
the wheels have no control over which direction the plane goes in. or wether it can stay still or not. if you have jet engine force pushing the plane to accelerate it there is nothing the wheels can do to stop it. doesnt matter if they are going backwards
 
when your wearing some roller skates and you try and run on the spot you dont go anywhere do ya. try running on the spot harder and you still dont go anywhere. its the same thing apart from the propulsion isnt directly connected to the wheels.
 
you would go somewhere, probably on the floor in pain :D

although skates is a totally different form of propultion, it uses initia rather then thrust.
 
well put it this way.

is the aeroplane on the floor to begin with................yes

are the wheels connected to the engines in anyways...............yes coz there connected to the plane and the engines are connected to the plane

do the wheels rotate faster as the plane gathers speed while the plane is on the floor...........yes

does the conveyer match the planes speed and in turn the wheels.........yes

therefore the plane cannot accelerate as the conveyer matches whatever speed the plane is going. so how can it move forward. the plane cannot accelerate whilst it is on the floor and the plane cannot get off the floor until it can move forward.

the propulsion has absolutly nothing to do with it, as long as it has wheels on the ground and they turn faster as the planes engines push the plane forward there is no way the plane can gather speed.
 
no man thats not right at all. its got nothing to do with the wheels or how fast they are moving, or the conveyor belt.
 
no, your not. The wheels are free spinning. there is no power to them at all.

Going by your theory, if the conveyor went in the opposide direction the wheels wouldn't spin and the plane would remain stationary :s.

has anyone got a treadmill? :D
 
the plane takes off iv explained it once and so has vbmenu_register("postmenu_111979", true); nizzanz1.. please stop saying it wont take off because the converyor belt is moving yada yada yada it could be going twice the speed of the plane the plane would still take off..
 
did you mean i have also explained it will take off? or i saying it doesnt?
anyway. the plane will take off, and on the airfield below, it will see many tiny figures scratching their heads thinking how did it do that? lol.
 
Back
Top