Brain Teaser

Discussion in 'Off Topic' started by csmguitarman, Oct 25, 2007.

  1. MBK2

    MBK2 New Member

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    If the truck travels 10 mph forward, not on the treadmill, and the treadmill goes in reverse 10 mph, wouldn't that make the plane travel more than the 10 mph you posed in your initial question?? Because you are now adding the pulling away of the truck as well. Because the treadmill, although spinning 10 mph, cannot move itself 10 mph forward as well, only the belt...so the tow truck itself is moving away from the treadmill.

    What if both the treadmill and the plane are pulled forward by tow trucks?? Thus making it equal again as you stated in your initial question.
  2. csmguitarman

    csmguitarman New Member

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    The tow truck question was posed with the planes engines off. what would happen. would the plane not be pulled forward even though the ground under it is moving backwards
  3. MBK2

    MBK2 New Member

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    See the biggest problem with your initial question and the answer that you are trying to shove down our throat is that... you stated that the treadmill would match the planes speed, basically as if you were saying that regardless of what propells the plane forward, the treadmill will match it.
    That being said, you are in fact saying that the plane would be spinning in place, because regardless of what moves the plane forward, the treadmill matches it in the opposite direction.

    That being the case, only the thrust of the planes engines would not get the plane airborn if it is basically stationary.


    But now you are trying to change the question to state that the jets' thrust would eventually out power the treadmill, causing the plane to move forward to attaing the 180 mph for lift-off.


    You are basically changing what you asked to make your explanation sound right...

    I'm sorry, but that's dumb if you are trying to say that was your initial question.
  4. goyleinlove

    goyleinlove New Member

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    Again, I think that 's the whole problem. The question changed and nobody told us
  5. csmguitarman

    csmguitarman New Member

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    AHHHH the jets dont out thrust the treadmill.

    The planes thrust does not transfer to the wheels. there is no force for the treadmill to counter act. what if you took the jets off the plane set them on wheels in place of the tow truck. tie a rope between them. Now if the treadmill matches the speed of the jets moving forward will the jets be able pull the plane. remember the jets are not on the treadmill.
  6. csmguitarman

    csmguitarman New Member

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    when did the question chage and what did it change to. If you are saying that the jets outtrust the treadmill......which i never said........then how is that possible since the treadmill matches the speed.
  7. MBK2

    MBK2 New Member

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    A tow truck pulling a car would have the same effect. You are pulling the plane 'AWAY' from the treadmill, away from the initial question. You are not adding the distance created by the tow truck pulling away from the treadmill itself into the equation.

    The better question would be, if the tow truck was instead a helicopter and it was pulling the plane at 180 mph forward, but the treadmill is matching the planes speed rearward....would the helicopter be able to pull the plane off the front of the treadmill??
  8. goyleinlove

    goyleinlove New Member

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    The initial idea was that the plane was moving forward at X miles an hour. The treadmill was moving =X in the oposite direction. X-(+)X=0. In order for the plane to ctually move it would have originally had to have been moving +X, not =X.
  9. csmguitarman

    csmguitarman New Member

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    you are still treating this like a car..... in a car the power is transfered from the engine to the wheels to the ground.

    in a plane the engine is transfered from engines to AIR. There is no ground. If a plane needed ground to move forward then once it lifted it would still need ground to fly. the wheels allow that tranfer to produce better accleration.
  10. goyleinlove

    goyleinlove New Member

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    I don't care how energy is transferred. This is a question of motion, not power.
  11. MBK2

    MBK2 New Member

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    No car...just a helicopter doing the pulling....what then???
  12. csmguitarman

    csmguitarman New Member

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    YES YES YES. Where does a tow truck apply its energy. TO THE GROUND. same the helicopter. exept helicopters apply that energy to the AIR.

    Cars move on land and the only way to change that is to alter that variable. move the ground and you change the way that car can move.

    If a car was on a treadmill doing 50 and the treadmill was doing 50 but forward and you took a radar gun to that car how fast would it say
  13. MBK2

    MBK2 New Member

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    If the helicopter appiles thrust thru air and it is pulling the plane forward 100 mph, but the treadmill is matching the speed in reverse 100 mph....are you saying that the plane would still eventually move forward to 180 MPH and take-off??
  14. goyleinlove

    goyleinlove New Member

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    Alright...

    We have to assume reality in the question. If the plane was moving at the same speed as the conveyer in opposite directions could the plane take off? That question states that the plane is on its wheels or there would be no need for it to take off. Apply that to my previous post and the answer is clear.
  15. csmguitarman

    csmguitarman New Member

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    Yes. Lets forget about taking off because i believe where we differ is if the plane will move forward.

    If you hold a toy car on a treadmill doing 10mph how fast are those wheels spinng. 10mph right. now i am not standing on the treadmill. if i push the car forward at 1mph the wheels will now be spinning at 11mph right.

    just say yes or no and i will give the rest of my analogy
  16. csmguitarman

    csmguitarman New Member

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    how the hell do you get motion..um power. things dont just move. a cars engine powers its wheels and that creats motion. are you telling me that is also true of a plane. A plane does not power its wheels
  17. MBK2

    MBK2 New Member

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    Helicopter pulling the plane using thrust of it's propellers thru air, pulls the plane 180 mph forward, but the treadmill matches the planes attempted speed and goes in reverse 180 mph.........

    What happens??

    Forget the car, let's talk Helicopters.
  18. goyleinlove

    goyleinlove New Member

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    Exactly. However the type of thrust is irrelevant in this instance. Motion is motion here whether there is a jet engine or a Buick motor. It can'tbe taken into account to answer the original question. Again, adding unnecessary variables.
  19. csmguitarman

    csmguitarman New Member

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    What matters is where that motion is applied. the ground or the air. I am not talking about the type of engine. you guys need to learn to read.

    When a plane moves down a runnway it is because it is tranfering its motion to the surrounding air. when a car moves down a runway it is because it is transfering its motion to the ground. am i correct?
  20. MBK2

    MBK2 New Member

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    Helicopter....Why are you dodging the helicopter??

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