No, You Can’t Have a Solar-Powered Passenger Plane

不,你不能拥有太阳能客机

Science, Spoken

科学

2024-07-29

7 分钟
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Guilt-free air travel is a beautiful dream, but there’s simply no way to get enough solar energy to keep a cabin full of people in the air.

单集文稿 ...

  • Today in science from Wired, at a recent rally, Donald Trump stated that electric planes could be a bad idea because you couldn't fly if it was cloudy.

  • I guess electric equates to solar energy in the former president's mind, which you know is actually great, just not so much for air travel.

  • Oh, solar planes have been around for a while, but they're probably not what Trump had in mind.

  • Theyre an ultralight aircraft, usually unmanned and carrying a single skinny pilot.

  • Its very unlikely that you will ever be a passenger on a solar powered plane that is delayed by clouds.

  • How can I be so sure?

  • Because physics.

  • Lets see why.

  • The next time youre riding in a car, stick your hand out the window flat with your palm down.

  • You should feel a backward pushing force from the interaction with the air.

  • Now tilt your hand slightly up.

  • Don't resist, just let the air push your hand up.

  • It feels like it wants to fly away, right?

  • Your hand is just like a plane wing.

  • What's really happening here?

  • Let's focus on one molecule of air interacting with your hand.

  • The molecule starts at rest.

  • Its velocity, or v, is zero.

  • Then your moving handwriting collides with air molecules and pushes it so that it moves downward and forward.

  • That molecule of air changed velocity, which means it accelerated.