why won't this thread die?

f you

TH

quote:

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why won't this thread die?

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I blame the tree hugging hippies.

effin bush.

So will it take off?

Uh, no.

Dang it.

I just knew it would.

I think it will

SHUT UP TOUCAN

It will take off.

If you think the wheels matter, think about this:

We have planes that take off on water. When the plane moves forward, the water moves at a velocity equal and opposite of the plane, relative to the plane (the same happens on the ground). If the plane was taking off in a river and going upstream, the water would be moving even faster in the opposite direction of the plane, but it would not matter (assuming the water does not cause any drag on the plane to prevent forward motion), the plane will still take off.

[This message has been edited by OneManArmy (edited 12/5/2006 1:49p).]

quote:

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Uh, no.

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The plane or this thread?

This guy is an expert.

ttt

The PLANE boss! The PLANE!

So, I just conducted this exact experiment in my back yard. I am happy to report that the plane took off.

I witnessed the experiment and can confirm Chuy's observations.



[This message has been edited by IIIHorn (edited 12/5/2006 4:03p).]

can I borrow your giant conveyor belt? You see...I've had this little fantasy that I have been meaning to try out.......

Im sick and tired of these ****ing conveyors on this mother ****ing plane.

So you would rather have a fancy conveyor instead of a plane one?

man, this thread will make 100,000 views by days end...

TTMFT

TTT

For Old Faithful.

MYSTERY

Ouch!

You got me!

185,000 views
and TTT

VideoAg-
Is there even an answer that you're withholding, or is is just a question that can't be answered? We should send this to Mythbusters!!!

Here is my answer:

If the velocity is measured from an observer not on the conveyor then of course the plane takes off.

If the velocity is measured by an observer on the conveyor then a problem arises in the formulation. You are trying to apply a speed constraint and a force constraint at the same time which doesn’t work. Consider just the velocity constraint first. It says that the axle velocity relative to the conveyor is equal to the conveyor velocity. This would require the wheel to stay in one place as observed by someone not on the conveyor.

Imagine standing next to the conveyor holding the axle of a tire as the conveyor rotates. You are holding the axle and tire in one position as it rotates. The velocity of the axle equals the velocity of the conveyor. The force it takes you to hold the tire in one place is equal to the friction between the tire and the ground. As you can imagine, this force wouldn’t be that great and it wouldn’t change as the conveyor speeds up. The only way for a plane to meet this requirement is to provide just enough thrust to equal friction. In other words the plane would not be at full throttle. Once you go to full throttle then the thrust force easily overcomes the friction force and the plane takes off. But you are violating the velocity constraint.

To summarize, the plane could take off but not under the velocity constraint.

YOU SUCK IIIHORN

OK, here’s another try.

Imagine one of the “people-mover” conveyor type walkways you see in large airports is set to move at a constant speed of 5 MPH.

Imagine also, a guy strapped to a skateboard using a powerful fan as his only propulsion. He has the fan set to move him at a constant 5 MPH.

If fan-propulsion-skateboard-guy is on the conveyor, facing opposite the direction of movement of the conveyor, does he move? (in relation to the area outside the conveyor)

Now, imagine that the speed setting for the conveyor and for the fan-propulsion system are synchronized, (speed up the fan to say, 10 MPH and the conveyor also speeds up to 10 MPH, etc…)

The analogies with ice and pulling on ropes, etc… are flawed. By “pulling on a rope” you are defining a change in dimensions as part of the problem (distance).

The plane does not take off.

What provides the velocity constraint?

Btw ...

The plane takes off.

We need a raspberry giving smiley.