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If (theoretically) I was sat at the back of an airplane which was travelling (constantly) at the speed of light, but then I walked down the aisle to the front of the plane to use the toilet, wouldn't I be travelling faster than the speed of light?

 

If so would I meet myself coming backwards? And would anyone even be able to see me in realtime? Cos I'm thinking, if I was moving faster than the speed of light then this would render me (in realtime) invisible to the naked eye?

 

Discounting the inherent variables of snakes (on a plane) and a ton of feathers (on the head), you'd all have to agree I've got a point would you not?

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Guest alex

Cosmonaut Sergei Avdeyev spent a total of 748 days on the Russian space station Mir during three separate missions. Because Mir was moving relative to Earth, it was also a time machine. Avdeyev is 0.02 seconds younger than he would have been had he never traveled in space.

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If (theoretically) I was sat at the back of an airplane which was travelling (constantly) at the speed of light, but then I walked down the aisle to the front of the plane to use the toilet, wouldn't I be travelling faster than the speed of light?

 

If so would I meet myself coming backwards? And would anyone even be able to see me in realtime? Cos I'm thinking, if I was moving faster than the speed of light then this would render me (in realtime) invisible to the naked eye?

 

Discounting the inherent variables of snakes (on a plane) and a ton of feathers (on the head), you'd all have to agree I've got a point would you not?

133416[/snapback]

 

:quotes:

Reading that with Kinky John's voice in my head made it bizarre.

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Cosmonaut Sergei Avdeyev spent a total of 748 days on the Russian space station Mir during three separate missions. Because Mir was moving relative to Earth, it was also a time machine. Avdeyev is 0.02 seconds younger than he would have been had he never traveled in space.

133421[/snapback]

 

The same goes for all of us according to your mate Bill Bryson. We all gain a miniscule amount of time when, say, we travel on a long haul flight. I know you won't believe this cos it was Bryson though. :quotes:

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If (theoretically) I was sat at the back of an airplane which was travelling (constantly) at the speed of light, but then I walked down the aisle to the front of the plane to use the toilet, wouldn't I be travelling faster than the speed of light?

 

If so would I meet myself coming backwards? And would anyone even be able to see me in realtime? Cos I'm thinking, if I was moving faster than the speed of light then this would render me (in realtime) invisible to the naked eye?

 

Discounting the inherent variables of snakes (on a plane) and a ton of feathers (on the head), you'd all have to agree I've got a point would you not?

133416[/snapback]

 

I'm flying on Friday. I'll do this and touch one of the stewardesses up on the way past. Watch the news on Saturday morning to find out whether I was invisible or not.

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Wouldn't you be too heavy to move?

133418[/snapback]

 

Theoretically I've been dieting for this exercise-I'm not carrying any extra timber, in fact I'm like a racing snake. I'm even wearing a tight vest top, which you'd like. I'm keeping it interesting for the non-science types and the gays tbh.

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Wouldn't you be too heavy to move?

133418[/snapback]

 

Theoretically I've been dieting for this exercise-I'm not carrying any extra timber, in fact I'm like a racing snake. I'm even wearing a tight vest top, which you'd like. I'm keeping it interesting for the non-science types and the gays tbh.

133427[/snapback]

:quotes:

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I'm flying on Friday.  I'll do this and touch one of the stewardesses up on the way past.  Watch the news on Saturday morning to find out whether I was invisible or not.

133426[/snapback]

 

At the speed of light? Which airline are you using?

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This is a basic way of describing it:

 

step one: plane's engines throttle up, increasing the force against the AIR behind the engines. no force is applied to the wheels

 

step two: increased force against the air pushes plane forwards

 

step three: conveyor belt starts turning the opposite way to the directon of the plane, meaning the wheels spin twice as fast as the plane is moving through the air

 

step four: the plane continues to accelerate, as does the conveyor belt, until the plane's AIRSPEED reaches, say, 160kts. At this point the wheels are spinning at the equivalent of 320kts

 

step five: plane takes off, because an airspeed of 160kts is more than enough to produce required lift on the wings

 

step six: wheel bearings probably melt, plane has trouble landing

133306[/snapback]

 

I can see what you are saying.

 

The engines suck the air over the wings. However this would create "hotspots" and not a uniform lift as the majority of the wing would not have any lift. Also its very dependent on the location of the engines. The ideal location being exactly in the middle of the wing, which is never the case as they are almost always located beneath them. This means the only air flow is under the wing and none above. Now in order to determine the pressure underneath depends on the speed of the air. Now you have to look into the compressable flow equations. Now assuming mach 0.999 airspeed through the engine this give a pressure of about 0.55atm below the wing compared to 1atm above. And hence no lift and the plane is infact forced to the ground

133333[/snapback]

 

Actually, it's a trick question, there is no possible "yes" or "no" answer, because the question is illogical. I just thought I'd play devil's advocate :quotes:

 

Basically, for the plane to move forward the wheels must be moving faster than the conveyor, yeah? But for the plane to move from it's station-holding position on the conveyor, as the thrust is applied to the engine, the wheels must turn quicker for it to develop forward motion. And according to the initial question, the conveyor will instantly match the speed of the wheels.

 

And that's the sticking point. As soon as the conveyor belt increases speed to match the plane's wheel speed, the plane's wheel speed will increase. It is impossible for the conveyor belt to ever be the same speed as the wheels of the plane once more-than-station-keeping thrust has been applied, and the wheels would instantaneously reach inifinite rotational velocity.

 

Thus, it's a bogus question. The circumstances described simply can't happen.

 

A better way to phrase the question, however, would be to replace "wheel speed" with "plane speed", as that is actually realistic... But that's for another day.

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I'm flying on Friday.  I'll do this and touch one of the stewardesses up on the way past.  Watch the news on Saturday morning to find out whether I was invisible or not.

133426[/snapback]

 

At the speed of light? Which airline are you using?

133432[/snapback]

 

:quotes: KLM.

 

Ok, speed of sound. I'll call her a bitch instead and see if she hears me.

 

Just as well you pointed that out, as I don't think my "You can't possibly have witnesses, I was invisible" defence would have stood up in court, on reflection.

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This is a basic way of describing it:

 

step one: plane's engines throttle up, increasing the force against the AIR behind the engines. no force is applied to the wheels

 

step two: increased force against the air pushes plane forwards

 

step three: conveyor belt starts turning the opposite way to the directon of the plane, meaning the wheels spin twice as fast as the plane is moving through the air

 

step four: the plane continues to accelerate, as does the conveyor belt, until the plane's AIRSPEED reaches, say, 160kts. At this point the wheels are spinning at the equivalent of 320kts

 

step five: plane takes off, because an airspeed of 160kts is more than enough to produce required lift on the wings

 

step six: wheel bearings probably melt, plane has trouble landing

133306[/snapback]

 

I can see what you are saying.

 

The engines suck the air over the wings. However this would create "hotspots" and not a uniform lift as the majority of the wing would not have any lift. Also its very dependent on the location of the engines. The ideal location being exactly in the middle of the wing, which is never the case as they are almost always located beneath them. This means the only air flow is under the wing and none above. Now in order to determine the pressure underneath depends on the speed of the air. Now you have to look into the compressable flow equations. Now assuming mach 0.999 airspeed through the engine this give a pressure of about 0.55atm below the wing compared to 1atm above. And hence no lift and the plane is infact forced to the ground

133333[/snapback]

 

Actually, it's a trick question, there is no possible "yes" or "no" answer, because the question is illogical. I just thought I'd play devil's advocate :quotes:

 

Basically, for the plane to move forward the wheels must be moving faster than the conveyor, yeah? But for the plane to move from it's station-holding position on the conveyor, as the thrust is applied to the engine, the wheels must turn quicker for it to develop forward motion. And according to the initial question, the conveyor will instantly match the speed of the wheels.

 

And that's the sticking point. As soon as the conveyor belt increases speed to match the plane's wheel speed, the plane's wheel speed will increase. It is impossible for the conveyor belt to ever be the same speed as the wheels of the plane once more-than-station-keeping thrust has been applied, and the wheels would instantaneously reach inifinite rotational velocity.

 

Thus, it's a bogus question. The circumstances described simply can't happen.

 

A better way to phrase the question, however, would be to replace "wheel speed" with "plane speed", as that is actually realistic... But that's for another day.

133438[/snapback]

 

Surely the point in a hypothetical question is that we take it as read that the initial information is complete and can be taken as fact though. I didn't realise we were allowed to question the initial premise based on the fact that it couldn't happen in reality. :quotes:

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I'm flying on Friday.  I'll do this and touch one of the stewardesses up on the way past.  Watch the news on Saturday morning to find out whether I was invisible or not.

133426[/snapback]

 

At the speed of light? Which airline are you using?

133432[/snapback]

 

:quotes: KLM.

 

Ok, speed of sound. I'll call her a bitch instead and see if she hears me.

 

Just as well you pointed that out, as I don't think my "You can't possibly have witnesses, I was invisible" defence would have stood up in court, on reflection.

133439[/snapback]

 

If you travel faster than the speed of sound, everything you say comes out backwards. That's why Concorde crashed: FACT.

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This is a basic way of describing it:

 

step one: plane's engines throttle up, increasing the force against the AIR behind the engines. no force is applied to the wheels

 

step two: increased force against the air pushes plane forwards

 

step three: conveyor belt starts turning the opposite way to the directon of the plane, meaning the wheels spin twice as fast as the plane is moving through the air

 

step four: the plane continues to accelerate, as does the conveyor belt, until the plane's AIRSPEED reaches, say, 160kts. At this point the wheels are spinning at the equivalent of 320kts

 

step five: plane takes off, because an airspeed of 160kts is more than enough to produce required lift on the wings

 

step six: wheel bearings probably melt, plane has trouble landing

133306[/snapback]

 

I can see what you are saying.

 

The engines suck the air over the wings. However this would create "hotspots" and not a uniform lift as the majority of the wing would not have any lift. Also its very dependent on the location of the engines. The ideal location being exactly in the middle of the wing, which is never the case as they are almost always located beneath them. This means the only air flow is under the wing and none above. Now in order to determine the pressure underneath depends on the speed of the air. Now you have to look into the compressable flow equations. Now assuming mach 0.999 airspeed through the engine this give a pressure of about 0.55atm below the wing compared to 1atm above. And hence no lift and the plane is infact forced to the ground

133333[/snapback]

 

Actually, it's a trick question, there is no possible "yes" or "no" answer, because the question is illogical. I just thought I'd play devil's advocate :quotes:

 

Basically, for the plane to move forward the wheels must be moving faster than the conveyor, yeah? But for the plane to move from it's station-holding position on the conveyor, as the thrust is applied to the engine, the wheels must turn quicker for it to develop forward motion. And according to the initial question, the conveyor will instantly match the speed of the wheels.

 

And that's the sticking point. As soon as the conveyor belt increases speed to match the plane's wheel speed, the plane's wheel speed will increase. It is impossible for the conveyor belt to ever be the same speed as the wheels of the plane once more-than-station-keeping thrust has been applied, and the wheels would instantaneously reach inifinite rotational velocity.

 

Thus, it's a bogus question. The circumstances described simply can't happen.

 

A better way to phrase the question, however, would be to replace "wheel speed" with "plane speed", as that is actually realistic... But that's for another day.

133438[/snapback]

 

Surely the point in a hypothetical question is that we take it as read that the initial information is complete and can be taken as fact though. I didn't realise we were allowed to question the initial premise based on the fact that it couldn't happen in reality. ;)

133442[/snapback]

 

Well, that was the way the question was phrased on various other forums where it caused uproar.

 

Thought I'd try it on here too :quotes:

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I'm flying on Friday.  I'll do this and touch one of the stewardesses up on the way past.  Watch the news on Saturday morning to find out whether I was invisible or not.

133426[/snapback]

 

At the speed of light? Which airline are you using?

133432[/snapback]

 

:quotes: KLM.

 

Ok, speed of sound. I'll call her a bitch instead and see if she hears me.

 

Just as well you pointed that out, as I don't think my "You can't possibly have witnesses, I was invisible" defence would have stood up in court, on reflection.

133439[/snapback]

 

There wouldnt be any reflection either. You'd be bombproof for a lightspeed grope. :quotes:

 

The point is (you complete moron) you would be seen ultimately-just not in realtime. There'd be a delay as to when you were witnessed groping her, but by that time you'd have made your escape-by parachute-from a plane travelling at the speed of light. Unless you stopped at the trolley for those pretzel things, in which case you'd be fecked.

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This is a basic way of describing it:

 

step one: plane's engines throttle up, increasing the force against the AIR behind the engines. no force is applied to the wheels

 

step two: increased force against the air pushes plane forwards

 

step three: conveyor belt starts turning the opposite way to the directon of the plane, meaning the wheels spin twice as fast as the plane is moving through the air

 

step four: the plane continues to accelerate, as does the conveyor belt, until the plane's AIRSPEED reaches, say, 160kts. At this point the wheels are spinning at the equivalent of 320kts

 

step five: plane takes off, because an airspeed of 160kts is more than enough to produce required lift on the wings

 

step six: wheel bearings probably melt, plane has trouble landing

133306[/snapback]

 

I can see what you are saying.

 

The engines suck the air over the wings. However this would create "hotspots" and not a uniform lift as the majority of the wing would not have any lift. Also its very dependent on the location of the engines. The ideal location being exactly in the middle of the wing, which is never the case as they are almost always located beneath them. This means the only air flow is under the wing and none above. Now in order to determine the pressure underneath depends on the speed of the air. Now you have to look into the compressable flow equations. Now assuming mach 0.999 airspeed through the engine this give a pressure of about 0.55atm below the wing compared to 1atm above. And hence no lift and the plane is infact forced to the ground

133333[/snapback]

 

Actually, it's a trick question, there is no possible "yes" or "no" answer, because the question is illogical. I just thought I'd play devil's advocate :quotes:

 

Basically, for the plane to move forward the wheels must be moving faster than the conveyor, yeah? But for the plane to move from it's station-holding position on the conveyor, as the thrust is applied to the engine, the wheels must turn quicker for it to develop forward motion. And according to the initial question, the conveyor will instantly match the speed of the wheels.

 

And that's the sticking point. As soon as the conveyor belt increases speed to match the plane's wheel speed, the plane's wheel speed will increase. It is impossible for the conveyor belt to ever be the same speed as the wheels of the plane once more-than-station-keeping thrust has been applied, and the wheels would instantaneously reach inifinite rotational velocity.

 

Thus, it's a bogus question. The circumstances described simply can't happen.

 

A better way to phrase the question, however, would be to replace "wheel speed" with "plane speed", as that is actually realistic... But that's for another day.

133438[/snapback]

 

 

You're not entirely right, as has already been mentioned lift could theoretically be generated with no forward movement of the plane. Having thought about this situation some more with the engines going full pult and the flaps on the wings forcing air down, (and hence plane up) a large amount of lift would be generated.

 

The stuff you are spouting about the conveyer and wheels is totally irrelevent since the question stated the conveyer would always match the wheel speed. SO if the wheels go infitiely fast the belt is too. Hence station keeping velocity is always equal to wheel velocity. I viewed is being that the wheel was trapped between two rolling metal tubes and spinning them so as engine speed increased the roller speed increased. Assuming no mechanical failures the the net plane horizontal motion would be zero. No matter how much thrust.

 

The real argument is can the engines also suck enough air around the wings to get the lift required. Then the plane would vertically take off until it was above the belt then bomb forward and take off like normal.

 

The other dodgy premises are the plane. Its like saying "i want a new combi boiler how much do they cost?" they are all different.

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