This will be my last explanation post in this thread… i think all the explanations have been covered at least once. so:
[quote=“SilverGT,post:437,topic:37377"”]
When you running on the treadmill in place do you feel any air?
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No. Now answer me this: When you’re running on a treadmill, how are you transfering force to the treadmill?
Do you feel air when youre running off a treadmill?
Again, what is transferring force to the non-treadmill surface?
im “ASKING” how fast is a airplane usually moving before it takes off?
depends on the plane type. Anywhere from ~50mph to ~170mph. Now, let me ask you this: How can a non-powered glider take off without any assitance from another vehicle?
at this certian speed doesnt the plane have air resistance for it to take off? the propeller/ jet engine like someone said only propell the airplane…this forward motion, not the propeller it self but the air resistance that it needs to lift the plane…
what?
so if the plane is on the treadmill with the jets/propeller at full speed…it doesnt have the air resistance it needs to lift off because there is no air resistance; the plane is not creating any air resistance.
the plane moves. movement creates AIRspeed which creates lift.
the plane has to be in physically motion … the physical motion means that its has air under its wings.
yes, exactly.
the only way it will fly is this
if you have the plane on a conveyor in a wind tunnel that replicates the wind speed it needs to take off at it will definitly fly.
I assume that you mean the plane is not physically moving through space in this scenario, right? if not, how is it getting lift is there is no wheel advancement?
When you are running on a treadmill, the thing that propels you is your feet pushing backwards on the treadmill.
When a plane is taking off, the thing that propels it is the jet engines pushing backwards on air.
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When you are running on a treadmill you don’t move forward because the thing you are pushing on is moving the direction you are pushing, hence no force and thus you don’t move.
When a plane on a treadmill is taking off, the thing it is pushing on (the air) is stationary, hence force and thus the plane moves.
If the plane and conveyor are moving the same speed then the plane is staying in the same spot not creating any lift.Lift is only created when air is moving
I dont think it will take off and i think they are going to mess this one up
they are not saying the plane will move(which it wont), they say “Will the plane take-off?”
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A plane is standing on a runway that can move like a giant conveyor belt. The plane applys full forward power and attempts to take off. This conveyer has a control system that tracks the plane’s wheel speed and tunes the speed of the conveyer to be exactly the same but in the opposite direction, similar to a treadmill.
Where does the lift come from then if there is no moving air?
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That’s the thing though, the whole point of the riddle is to try and get people to understand that, despite the treadmill, the plane moves just fine because it is propelled by the thrust of the engines, not the turning of the wheels.
Lets say you have a propeller plane sitting on the ground in a hurricane. The wind is blowing at the plane at the same flow speed as the propellers can push air. If you turn the plane on and go full speed with the props, does the plane lift off the ground?
“If a plane is traveling at takeoff speed on a conveyor belt, and the belt is matching that speed in the opposite direction, can the plane take off?”
So if they are traveling the same speed,the plan is staying in one place. Lift can only be created with air moving.No air moving=No lift.If you run on a treadmill you feel no air moving because you’re stationary.If you run on the road you feel air because you’re moving forward.
If you run on a treadmill you feel no air moving because you’re stationary.If you run on the road you feel air because you’re moving forward.
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Very wrong
You feel no air because you arent moving foreward, because your propulsion (your feet) is relative to the ground, meaning your feet push you foreword, so on a tradmill, that force is negated
On a plane, the foreword motion is provided by the engines, which is NOT relative to the ground. The engines will always push foreward, because there is NO mechanical connection between them and the ground
Dumb it down ever further:
The motion of a plane has only to do with air being pushed away from it by the engine, causing a reaction, moving the plane foreword. The motion of the ground has NOTHING to do with that
If it was a car, it would be different. It wouldnt move, because there IS a connection between the carls propulsion system (the wheels) and the ground
Wrong. The treadmill exerts no force on the plane, only spins the wheels freely. The plane moves forward completely uninhibited by the treadmill.
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If the plane stood still, the conveyor would carry the plane away even when the wheels spin freely.The plane matches the speed of the conveyor wouldnt the wheels be traveling the same speed as the plane and keeping it in place? Thats what im thinking.