SixPapaCharlie
May the force be with you
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What do you think will happen? Then watch the video. I totally guessed wrong.
My guess, the drone may drop a skitch but it continues to hover. After all, the elevator is moving the air up along with the person and drone. Now I'll watch and see if I guess correctly...
The issue here is that elevators aren't sealed and there's acceleration. Air moves through them vertically as the elevator moves up and down. The drone will remain fixed relative to the air its in, which will move some as the elevator goes up and down. Even if it were sealed, there'd be some movement (but less) due to inertia and the acceleration.
Not quite the taking-off-on-a-treadmill "scenario" lol
Sure, but that's a bit too simple. If the drone is powered off, sure... But shaking the ping pong ball induces far more acceleration, so of course it'll rattle around, and the ping pong ball isn't producing lift, doesn't have a computer providing stability control with 3D gyros, and won't eventually enter ground effect as the elevator climbs.Wouldn't even matter if it was sealed. Put a ping pong ball in a sealed glass jar and shake it around. I bet it rattles. And a ping pong ball will be more affected by air movement (or lack of) than a drone will. Density and all that.
Sure, but that's a bit too simple. If the drone is powered off, sure... But shaking the ping pong ball induces far more acceleration, so of course it'll rattle around, and the ping pong ball isn't producing lift, doesn't have a computer providing stability control with 3D gyros, and won't eventually enter ground effect as the elevator climbs.
Acceleration? Aren't those drones just using sensitive accelorometers?This is what I thought.
I am still not 100% sure why.
Correct. Once acceleration ceases and inertia has done its thing, it will find homeostasis and will move with the mass containing it. A ping pong ball being rattled never gets that opportunity.Even a drone in a sealed container is bound by Newton's Laws.
Next video: "What happens to the bullet when a gun is fired in an elevator"
Dry cleaning. Don't forget the dry cleaning.Damaged hearing, arrest, court date, jail time.
We are in agreement. The way I read your first post was that the drone shouldn't move up or down at all when the elevator accelerated because the air would 'encase' it like it was in the middle of a jello mold.Correct. Once acceleration ceases and inertia has done its thing, it will find homeostasis and will move with the mass containing it. A ping pong ball being rattled never gets that opportunity.
Gotcha... and I sure hope not. I wouldn't want to be in that elevator, at leastWe are in agreement. The way I read your first post was that the drone shouldn't move up or down at all when the elevator accelerated because the air would 'encase' it like it was in the middle of a jello mold.
Gotcha... and I sure hope not. I wouldn't want to be in that elevator, at least
Why why why do I keep getting sucked into these threads..???
What would the results be if the elevator was in zero gravity as in the space station.??
I dunno. Depends on the flavor of Jello.
Why would you need an elevator in zero gravity?
What would happen if the drone were on a treadmill in the elevator?
This is what I thought.
I am still not 100% sure why. Does all the air suddenly go to the floor in an elevator when it ascends? I know air is compressible and I would have expected a brief dip / bump but not that much.
Forget the air... It's not having the greatest effect on things. It's all about acceleration.
If we use the elevator as our frame of reference, essentially what we're doing when we start down is we're turning gravity down, to maybe 0.8 or 0.9 G. Since the drone is pushing enough air down to counteract exactly 1 G before the elevator starts moving, and now we're subjecting it to less than 1 G, it goes up. Same is true if the elevator is going up, and then stops at its destination.
The opposite is true when we stop going down, or start going up - We're effectively turning gravity up a little bit, to maybe 1.1 or 1.2 G. Since the drone was pushing enough air down to counteract only 1 G and now it's "heavier" it will go down.
Now, let's say you're riding an elevator up the Burj Khalifa, all the way from the ground floor to the 163rd floor, and that it's a normal-speed elevator that just accelerates for a couple seconds and then goes at a steady speed until decelerating for a couple of seconds. If you wait to start the drone until after the elevator is finished accelerating, you'll have a significant amount of time where the drone will fly completely normally, as if you're just in a small room rather than an elevator. It won't act different until the elevator starts to decelerate.
Make sense?
We are not subjecting it to less than 1 G unless it is touching the elevator and the elevator moves.
[snip fascinating discussion of hairdryer and ping pong ball video]
I forget where I was going with this but I don't think you are changing the G force by moving the elevator unless the drone is resting on the elevator floor.
Oh yeah, the drone is not pushing itself off the floor, it is just climbing the air molecules.