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Doing a bit of research I found a few sources that say that the terminal velocity for a generic smartphone is ~20-40mph, which isn't that much. Lots of phones survive car crashes with higher speeds than that. Add to that landing on softer soil and maybe even breaking fall with branches and I'm not shocked it survived.

No screen crack is pretty good though. Smartphone screens have gotten crazy good recently




First, hat tip for terminal velocity research. That is a nice addition to this discussion.

I was thinking exactly the same about the landing. If it lands in a soft place, like tall grass, most phones should be fine. Most phones are broken by falling onto hard surfaces.


> No screen crack is pretty good though. Smartphone screens have gotten crazy good recently

It looks like it has an intact screen protector. The impact does not appear to be that strong.


There's no way it's 20-40 mph. They're dense enough for much higher velocities.


~25mph assuming a Cd of 2.1 (a smooth brick is the closest I could find) a mass of 0.194Kg and a surface area of 0.01142313m^2 (75.6mm x 150.9mm).

Of course that assumes it’s falling facing its largest surface, and not tumbling or a falling edge first. Obviously that is trickier to calculate, but 20-40mph doesn’t seem that unreasonable.

Edit: it takes ~3 seconds to reach 99% terminal velocity.


> Of course that assumes it’s falling facing its largest surface

That was what I was thinking: surely it wouldn't be stable falling face-first? Wouldn't it be more likely to either tumble or settle on an edge?


> Wouldn't it be more likely to either tumble or settle on an edge?

There's also the possibility that it behaves more like an airfoil, and starts generating lift once it's going fast enough.


This feels like calculating a "spherical horse in a vacuum", except with drag this time.


Hah, yeah. But it's a good problem solving and reasoning exercise. One of my courses in college used this book and it's very useful for reasoning about general real-world science topics: https://uscibooks.aip.org/books/consider-a-spherical-cow-a-c...


First Monday morning back email avoidance tactics ;)


They’re also broad and flat, and very likely to tumble unaerodynamically on their way down.


Confirmed on wolframalpha. Terminal velocity is about 9mph

https://www.wolframalpha.com/input?i=terminal+velocity+of+an...


1.28sqm projected surface area? That's a very a big iphone.


>a very a big iphone.

putting mildly, still it's lovely to see the mix the input of imperial and metric units.

the 'fluid' density is quite wrong as well. 1.29 kg/m^3 -> almost 777 times lighter than water, it's similar to air. By its dimension iphone 15 should be around twice heavier than water.


Exactly one iphone had a mass that low, 5s. None of them have >1m^2 surface area.


That's assuming the phone will fall while facing down with it's largest surface.


9mph? Always carry an iPhone while on an airplane ...


20 MPH? If it's... attached to a parachute?


Light. Big screens. High drag to weight ratio.


Made up numbers.




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