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-   Off Topic Chat (https://www.seccs.org/forums/forumdisplay.php?f=10)
-   -   Physics question (https://www.seccs.org/forums/showthread.php?t=3922)

cody 2005-11-28 08:24 PM

It might have somthing to do with number of members each forum has... :P

Nick Koan 2005-11-28 08:26 PM

Quote:

Originally Posted by JC
Ya well half of us are engineers and one of us is an airplane designer. :p

and one of us is an engineer who is extremely bad at physics.

/tries not to look at self in mirror

Kevin M 2005-11-28 09:03 PM

Quote:

Originally Posted by BAN SUVS
Okay now I get it. The conditions of the question cannot be met with an aircraft.

Do I get a cookie for saying this first? (As far as I know; I only read the first page of the nabisco thread)

Ezdno 2005-11-28 11:45 PM

What kind of cookie would you prefer?

M3n2c3 2005-11-29 07:40 AM

Quote:

Originally Posted by cody
It might have somthing to do with number of members each forum has... :P

Does someone want to figure out the ratio of registered members to pages or posts in the respective threads? :lol:

Quote:

Originally Posted by JC
Ya well half of us are engineers and one of us is an airplane designer. :p

I am most certainly not an engineer, hence my absence from the technical parts of the discussion :oops:

MPREZIV 2005-11-29 07:47 AM

makes sense to me: plane not moving, air not flowing over wings, no lift, no flight.

the tires could be going as fast as you could imagine, and with no air over the wings for lift, the thing won't leave the ground.

(scratches head)

M3n2c3 2005-11-29 08:12 AM

Quote:

Originally Posted by MPREZIV
makes sense to me: plane not moving, air not flowing over wings, no lift, no flight.

the tires could be going as fast as you could imagine, and with no air over the wings for lift, the thing won't leave the ground.

(scratches head)

I think the general idea that our aerospace engineers here are trying to get at is that there's really no way a conveyor belt could stop a plane from moving, since a plane uses thrust from the turbines to move, not rotation of the wheels. The real confusion is coming from the poor wording of the problem. The idea is improbable in the first place. :P

Now, if a Subaru was on a conveyor belt. . . :lol:

doubleurx 2005-11-29 09:47 AM

Me for the win - post #6.

sybir 2006-01-21 10:45 PM

Here we go again ;)

http://www.i-club.com/forums/showthread.php?t=124084

Blame Ed :p

doubleurx 2006-01-23 09:28 AM

Oh my god. People cannot think! I couldn't get past the second page.

Ouch!

A1337STI 2006-03-08 10:57 AM

lamo air speed =0 of the needed 150. no take off. period. ;) easy one (course i've taken hang gliding lessons)

assume the needed Air wing speed for take off is 150 .

the aircraft engine sends thrust backwards , this pushes the air plane forwards.
as the plane starts to move forward (1 mph) the weight of the plane still bares down on the tires, the friction between the conveyor belt and the tires is great or than the friction of the wheel bearing (assuming no brakes are applied) the wheel rotates . the rotation of the wheel triggers the conveyor belt to move backwards at 1mph. thrust is still applied so the plane again moves forward and repeat.

with a jet engine there is not a great deal of air flow Over the wings by the jet engine alone, wings produce no lift . you've just created a very Inificient fan.

If its a propeller in front of the wings you will have air flow over the wings and create lift and you will take off with a ground speed of zero if you can manage to get the air moving fast enough around your wings.
so it should depend on engine placement.

also by exact definition of the question. if you locked your tires up, and the trust of your engine was enough to overcome the friction of the tires(lockedup) you'de slide them (not rotate) and the convyer belt wouldn't start up... ;)

(please at least post back the correct answer for the thread is locked )

Dean 2006-03-08 11:00 AM

Please lock this thread and let it die...

JonnydaJibba 2006-03-08 11:15 AM

:?:

Nick Koan 2006-03-08 11:19 AM

Quote:

Originally Posted by Dean
Please lock this thread and let it die...

I'm almost tempted to lock all the old threads now...

JC 2006-03-08 11:20 AM

Quote:

Originally Posted by A1337STI
(please at least post back the correct answer for the thread is locked )

Quote:

Originally Posted by JC
No, I'm an aerospace engineer. I should know.

Quote:

Originally Posted by JC
If your wheels are moving at the same speed as the treadmill, apply a no slip condition then the plane isn't moving regardless of how you are applying thrust. If the plane doesn't move, you don't take off.

FTW

cody 2006-03-08 11:23 AM

Loud Noises!!!

Evo Mike 2006-03-08 12:20 PM

it shouldn't be able to take off.... i hated physics by the way.

MPREZIV 2006-03-08 12:22 PM

Why are we on this again?


i just got a nose bleed...

sperry 2006-03-08 12:30 PM

HOLY JESUS PEOPLE.

As originally written the question has no solution, there is a logical block in the wording.

As it should have been written, the plane will take off, with a wheel speed twice that of the airspeed.

Please read the thread before restarting this nightmare of an argument.

JonnydaJibba 2006-03-08 12:36 PM

I don't know why we're yelling!

cody 2006-03-08 01:13 PM

:lol:

JC 2006-03-08 01:29 PM

Quote:

Originally Posted by JonnydaJibba
I don't know why we're yelling!

We can't hear each other over the rod knock from your car!

A1337STI 2006-03-09 04:11 PM

my bad. lets lock the search button ...

JonnydaJibba 2006-03-10 08:43 AM

Quote:

Originally Posted by JC
We can't hear each other over the rod knock from your car!

Ooooh. You cut me deep on that one.

dknv 2006-03-10 11:56 PM

I was gone somewhere when this discussion was taking place. Otherwise, I would've put my simplistic answer as such

For every action there is an equal and opposite reaction.

Since an airplane, by our typical definition of terms, is assuming the reaction is a stable ground, no, the plane will not take off on a conveyor belt.

--> this person has never taken physics, but remembers stupid memory joggers.

T'was a good discussion all over the place anyway.


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