I made the correction right after F U I have to ask now am I uninvited to be a GRUNT on Thanksgiving? :idea:
Of course not, we'll just stay away from any conveyer belts near the boat ramp.........
Of course not, we'll just stay away from any conveyer belts near the boat ramp.........
That`s a dreaded sight when sitting back admiring your unintelligent post and then insult to injury------CAN`T SPELL Thanks man will be in contact, but must say it hurt
Here's the original post.
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
"...tracks the plane's speed..." It states right there that the plane has speed. Plane can't have speed if it isn't moving.
"...tunes the speed of the conveyor to be exactly the same..." Again, the plane has to be moving to have a speed for the conveyor to match.
Still wrond?
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
First:
Tracking speed. This is a measurement of rate of change is location. If you are walking on a treadmill it does not tell you your speed. It tells you your equivilent speed. Lets assume that speed is being measured by GPS. The plane speeds up to some speed (you pick how fast). The conveyor starts, going the opposite direction at the same speed. You will not see a change in the speed of the airplane, you will see the rpm's of the wheels double which is totally meaningless to the question. The plane flies normally.
second:
The question states the treadmill goes the opposite direction at exactly the same speed. What you end up with is two independent things travelling in opposite directions. If you think about what you are saying the plane has to take off normally. If speed is a measurement of change in location then the plane has to be moving from point a to point b in order for the conveyor to be running at all. If the conveyor matching speed means the plane is not moving then the conveyor would have to stop. The conveyor and the plane are totally unrelated to each other exept the effect that the speed of the conveyor has on the rpms of the wheels. If you are in a car and do a burn out, the speedometer indicates a speed much faster than the vehicle is actually travelling. I say again. The plane will take off normally.
The plane doesn't need traction. IT IS NOT PROPELLED BY THE TIRES, the tires are free to spin as the plane moves forward by THRUST from either the jet engine or the propellers. The fact that there is a treadmill spining under the tires means NOTHING. Replace the treadmill with ice, no traction, ZERO, the plane will still move forward from the THRUST of it's power, the tires can slide along, or they can turn, the tires are only holding the plane up and have nothing to do with forward motion. If the treadmill was moving at 5 times the planes speed, it means NOTHING as the wheels would just SPIN along under the plane as it MOVED forward. Some here are obsessed with the wheels, and the treadmill canceling the forward motion, it will not cancel the forward motion, it will only spin the tires faster. Tires that WILL NOT STOP THE PLANES FORWARD MOTION unless you apply the brakes. The tires are independent to the planes motion, just FREEWHEELING along. Would the treadmill move the plane forward if it was going the same way?????? NO!!!!!!!!!!!!! Because the tires are FREE SPINNING under the plane, regardless of which direction the treadmill is turning them, the jet/prop is still the planes one and only means of ANY MOTION at all...........Any trick reading of the question, like the plane has no wheels, or the plane is sitting there somehow attached to the ground is out of the scope of the intent of the question.......The MFer WILL FLY...........
I have to admit.......you make a very good argument to the question. :boxed:
For A V-drive guy to say a jet is very powerful is a hard thing to do.
I can see how the friction of turning the wheels the opposite way is not great enough to slow the plane enough to cause the plane not to move forward......because the jet is powerful and there is no conveyor in the world that can rotate fast/quick enough w/850,000 pounds of rolling plane on top of it. That would be realworld.
Soooooooooo....Eventually, with enough groundspeed/airspeed......She'll fly. :crossx:
If the plane is standing on the runway and thrust begins to move the plane forward then the treadmill moves in the opposite direction negating forward motion. Have you ever walked backwards on an escalator? When you run on a treadmill for exercise, you match the speed of it and you do not run off the edge. I realize thatwheels have nothing to do with the plane flying but uses them to roll down the runway with thrust from the engine. Now here think of walking backwards on an escalator or a moving sidewalk. The plane needs airflow over the wings by gaining speed down the runway till it has lift.
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
First:
Tracking speed. This is a measurement of rate of change is location. If you are walking on a treadmill it does not tell you your speed. It tells you your equivilent speed. Lets assume that speed is being measured by GPS. The plane speeds up to some speed (you pick how fast). The conveyor starts, going the opposite direction at the same speed. You will not see a change in the speed of the airplane, you will see the rpm's of the wheels double which is totally meaningless to the question. The plane flies normally.
second:
The question states the treadmill goes the opposite direction at exactly the same speed. What you end up with is two independent things travelling in opposite directions. If you think about what you are saying the plane has to take off normally. If speed is a measurement of change in location then the plane has to be moving from point a to point b in order for the conveyor to be running at all. If the conveyor matching speed means the plane is not moving then the conveyor would have to stop. The conveyor and the plane are totally unrelated to each other exept the effect that the speed of the conveyor has on the rpms of the wheels. If you are in a car and do a burn out, the speedometer indicates a speed much faster than the vehicle is actually travelling. I say again. The plane will take off normally.
Don't read so much into the original question. You rewrite it and rethought it to where it's two paragraphs long:rollside: Just go to the mall and walk backwards on an escalator, at the same speed but in the opposite direction and see how much forward motion you get. You can further investigate the theory by flapping your arms and see if you can fly :rollside: :rollside:
If the plane is standing on the runway and thrust begins to move the plane forward then the treadmill moves in the opposite direction negating forward motion. Have you ever walked backwards on an escalator? When you run on a treadmill for exercise, you match the speed of it and you do not run off the edge. I realize thatwheels have nothing to do with the plane flying but uses them to roll down the runway with thrust from the engine. Now here think of walking backwards on an escalator or a moving sidewalk. The plane needs airflow over the wings by gaining speed down the runway till it has lift.
How does the conveyer "negate" forward motion? By turning the WHEELS? Screw the wheels, they add or subtract NOTHING to forward motion because they TURN. Are you people just messing around? or do you really think what you're typing? The MFer WILL proceed down the runway and take off just as though the treadmill wasn't there, it is called THRUST. As I mentioned before, would the treadmill move the plane forward if it was running the same way? Hell NO............If you were wearing roller skates on an escalator you could just Fn stand there, and NOT MOVE.......OK, lets try this: Airport conveyer, "people mover", you are wearing skates. you could stand there and not move, (although the people that weren't wearing skates would run into you), or you could actually propel yourself AGAINST the mover and go the OTHER way, (again, the people without skates would be at risk), or you could turn around and stand there and still not MOVE, or skate with the mover and your speed would be the same as when you skated against the mover.......The ONE AND ONLY DIFFERENCE would be wheel speed...................I think you guys are just F'n with the people here that have a grip on reality..........Remember, "engineers" drive TRAINS....MP
I thought this was covered in another thread title, "Sunk the boat"
Wasn't this supposed to be a Poll?
Brian
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