PLS i need 1 question answered: (physics)

Have you ever seen hellis in space?

of course not in space
actually with gravity BUT without air..

will it fly ? i think it will not, you ?

Use your head op... You know the answer... It's brutally obvious.

Why do birds have wings instead of farting out a blast of propulsive energy from their bums?

depends what the rotating blades are made out of, unless they are designed for anti-gravity flight they will not be of any use in an airless environment

If you put a jet liner on a treadmill would it take off?

LOL, all these questions!

Ahhh I have a better way to open your mind OP...

If I sucked all the water out of a swimming pool, could an fish still swim around in the pool?

yes, 2+2 = 4

Helicoptor on a turntable that spins as fast the rotor blades turn, will it take off?

it would be swimming in air :)

An helicopter will not fly in a vacuum, for the same reason it can not fly above a specific altitude to rescue the everest people. The air is to thin to support the helicopter.

What if the air was 100% Humidity?

OP could be a kid, so I'll help. The Answer is no. The rotors generate an air pressure differential, high underneath, and low above. The high air pressure generated below pushes the rotor blades and thus the Heli upwards.

Last Edited by Richard Eldritch on 06/09/2010 04:36 AM

Fascinating! Hmmmm almost how a bird.... or even a HELICOPTER, might swim through the air! :)

no, assuming the direction of the turntable is the same as the rotation of the blade. relative to the air the blade is passing through it will be stationary.

What about if the helicoptor was upside down and the blades span in the reverse direction, Whilst it was on a turntable that spins in the same direction as the rotorblades?

ok, lets take the RC chopter model variant
we give it into a room where we suck all air from it
it is on earth, it is made of glass, we see in, gravity is making the work as always..

now we turn on the electric motor.. and it generates motion
this motion of the blades has 0 resistance..

it must generate some from of energy (+ energy from this rotation) ?

Your help, if the OP is in a fact a kid, doesn't offer much for personal discovery. You didn't answer either why it wouldn't work in a vacuum.

Hence why I'm trying to stimulate him with my talk of fish in empty pools and birds that shoot flames out of their bums! ;)

If you get a radiation shielded box and put a cat in it, but had a gas canister release trigger inside that is activated by the radiactive decay of a single atom, what happens if you leave it for 5 minutes is the cat alive or dead?

Let see.. I reckon it would be pushed down on to the turntable, then flung sideways from it by the gyroscopic force!

OP, it doesn't matter that there is gravity!! Haven't you read a word I've said!

Here is the answer:

Air is MADE OF MOLECULES.

The only reason a bird, or a helicopter can fly, is because they use the air to "push" themselves upwards.

A bird is literally "swimming" in air.

So if I create a vacuum, and there is no more molecules in the box, how is the helicopter going to fly?

It won't.

no, it needs wind resistance. no air in a vaccum. in a vacuum a feather will fall at the same rate as a penny.

Both! untill you measure (observe) it...

To further increase your understanding OP...

When we drive in a car, and drive fast, what does it feel like when you stick your head out of the window?

You get smacked in the face with air molecules... the speed of the car has increased the rate at which you are making contact with the air.

Because outer space is a vacuum, that is why you can fly at speeds that are 1000 fold faster then you could ever travel on earth.

Without all those molecules hitting your vehicle, there is nothing to slow you down or "drag" you.

Have you seen a spaceship coming back into the Earth's atmosphere?

The spaceship is traveling so fast coming back to the Earth, that when the air molecules start hitting the spaceship, it becomes red hot, from all that friction!

If I could move you through the air fast enough, I could tear all the flesh from your bones.

Boyle's law OP, MOTHERFUCKING LEARN IT!

There is no spoon/cat!

understood :D

i preffer human psychology before all other sciences, it was a idea, that it can generate, heat or something, even if its in vacuum, but indeed heat is also a preference of air is it ?

Are you chuck norris?

No.. Bernoulli Principle

LOL
chuck has human flesh on his exoskeleton ?

"preference" isn't a correct word to use here in this context, but I understand what you mean...

So yes, you need air, or again, molecules, to transfer heat, from one molecule to another.

Only light and other wave energies can transmit themselves through a vacuum... light becomes "heat" only when it contacts some molecules, like us on earth.