Intrepid.com.au

I came across an interesting physics thought experiment. There are lots of sites discussing it but it seems to have originated here.

A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?

This answer seemed obvious to me at first, the plane does not take off because the conveyor belt keeps the plane stationary preventing the planes wings from getting lift. This is incorrect. The thing that confuses people, including me at first, is that the movement of the conveyor does not keep the plane stationary or move it backward, it just spins the wheels. Because the wheels are spinning faster the wheel mechanism will generate more friction than normal, but this would not be enough to prevent the plane from taking off.

So basically, the plane needs its normal take off thrust plus some additional thrust to over come wheel mechanism friction in order to take off. If you assume the system is frictionless then only normal thrust is needed. That’s my understanding anyway, what do you think?

If this is true it could be the biggest development in medicine, possibly ever. I say if it is true because you just cant blindly believe anything you read or hear in the media these days, but thats a whole other blog post. Basically a 69 year old from ohio had the tip of his finder severed by a model aeroplane propeller. His finger was treated with ‘Pixie Dust’ then his finger tip grew back in just four weeks. Yes the whole thing finger grew back without scarring as if the injury never happened. It sounds too good to be true and with the medias history of picking up fake news I’m somewhat skeptical. I’m keeping an open mind though in the hope that it is completely true, because if it is it could be an amazing advance for the human race. Just imagine for a moment being able to regrow limbs, or even better being able to re-grow failing or diseased organs.