A fun theoretical question.

[sar104]

If the drone’s forward velocity can match or exceed the speed of the train, no problem. When he stops the drone in the video it looks like it flying backwards when he catches it, but it is then moving slower than the train (and the pilot).

The speed of the train is completely irrelevant in that example - all the drone knows about (figuratively speaking) is the air around it, which is moving with the train.

 

[Ken K]

Well in fairness you are talking about gravity and relativity. Where as I was talking about the technology associated with the gps and if the moment the legs left the ground would the drone attempt to hold gps position.

Hi mb. Didn't mean anything negative or contradictive to your post. Just thought the visual might get a few chuckles.
Have a great day.

 

[vanderzyde0]

So, if you are in an enclosed vehicle, at 75mph, and you hold a tennis ball up on the interior roof and let go, what happens?

Does the tennis ball have gps?

 

[Jackcutrone]

In keeping with yhe "fun" part of this thread, if you are going to try this be sure to calibrate your drone's compass first!

I think you should also make sure your life insurance is paid up first too.

 

[CrashSteve]

The drone would be moving exactly as fast as anything else inside the vehicle—including the air mass. That’s why flies or bees, for instance, are able to fly about inside vehicles while they’re moving. If you drop a ball inside a bullet train going 180mph, it will NOT suddenly hurtle toward the back as it’s also moving at that speed relative to the ground. It would simply drop straight down. If this weren’t true, I would be very afraid to have a meal inside that train as, if I were to drop my steak knife, umm, yeah: right into my chest at 180mph!

 

[rmb]

Hi mb. Didn't mean anything negative or contradictive to your post. Just thought the visual might get a few chuckles.
Have a great day.

Omg Ken K. No negativity perceived!
I just wanted to make sure that I was expressing myself properly

It’s funny I have started posts of far more importance and not gotten the traffic that this has generated.

What a crackup[emoji12]

 

[rmb]

The drone would be moving exactly as fast as anything else inside the vehicle—including the air mass. That’s why flies or bees, for instance, are able to fly about inside vehicles while they’re moving. If you drop a ball inside a bullet train going 180mph, it will NOT suddenly hurtle toward the back as it’s also moving at that speed relative to the ground. It would simply drop straight down. If this weren’t true, I would be very afraid to have a meal inside that train as, if I were to drop my steak knife, umm, yeah: right into my chest at 180mph!

Ah, but again the flies and bees do not have 16 satellites trying to hold them to a set of gps coordinates

 

[FoxhallGH]

Does the tennis ball have gps?

If GPS stands for 'Green Playing Sphere' - then yes ...

 

[FoxhallGH]

Ah, but again the flies and bees do not have 16 satellites trying to hold them to a set of gps coordinates

Nope - they talk to the trees - and there's lots more of them!

 

[Goldengate98]

The speed of the train is completely irrelevant in that example - all the drone knows about (figuratively speaking) is the air around it, which is moving with the train.

If-a-drone-hovers-steadily-in-a-stationary-train-and-the-train-starts-moving-will-the-drone-move-backwards-with-respect-to-a-passenger-on-the-train

 

[Goldengate98]

The drone would be moving exactly as fast as anything else inside the vehicle—including the air mass. That’s why flies or bees, for instance, are able to fly about inside vehicles while they’re moving. If you drop a ball inside a bullet train going 180mph, it will NOT suddenly hurtle toward the back as it’s also moving at that speed relative to the ground. It would simply drop straight down. If this weren’t true, I would be very afraid to have a meal inside that train as, if I were to drop my steak knife, umm, yeah: right into my chest at 180mph!

Funny image of the steak knife! (I gotta list of people if that were only true) The only observation is that if I drop the knife while moving at 180mph it would drop straight down from my perspective on the train. But the moment I let go, the force moving it forward drops to near zero and it begins to decelerate relative to me and the train. From outside the train it looks like its falling in an arc.

 

[sar104]

If-a-drone-hovers-steadily-in-a-stationary-train-and-the-train-starts-moving-will-the-drone-move-backwards-with-respect-to-a-passenger-on-the-train

In the example under discussion the train is moving at a steady velocity. In the discussion that you linked to the train is accelerating from rest. Those are completely different situations.

 

[sar104]

Funny image of the steak knife! (I gotta list of people if that were only true) The only observation is that if I drop the knife while moving at 180mph it would drop straight down from my perspective on the train. But the moment I let go, the force moving it forward drops to near zero and it begins to decelerate relative to me and the train. From outside the train it looks like its falling in an arc.

No - that's incorrect. There was no force moving it forwards if it was traveling at constant velocity, and so it will not decelerate. Newton's first law.

 

[DesG]

All we need is a volunteer with a disposable mavic to sacrifice all in the interests of science and a good laugh.

 

[Flycaster]

Or.......
If you are in an enclosed vehicle, at 75mph, and you spill your fresh cup of HOT coffee onto your lap, what happens?

I scream like a B****

 

[Ken K]

I scream like a B****

It's OK to say "Banshee" here, I think.

A banshee or bean-sídhe is a female spirit in Irish mythology who heralds the death of a family member, usually by wailing, shrieking, or keening

 

[Flycaster]

It's OK to say "Banshee" here, I think.

A banshee or bean-sídhe is a female spirit in Irish mythology who heralds the death of a family member, usually by wailing, shrieking, or keening

True, but the former makes for a better "mental image"....