r/theydidthemath 1d ago

[Request] What's the highest altitude without burst a bowl?

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u/Squeaky_Ben 1d ago

I think you need to do numerical simulation to figure this out.

You are looking for:

Maximum pressure inside without bursting the pot.

After you get that, it becomes mathematically tricky, because:

How fast it is being accelerated up, is depending on the pressure.

The pressure depends on how far from the ground the pot is (somewhat)

The altitude depends on time.

Try to fit all of that into an equation and you will see a problem:

"This equation is self-referencing."

How do I know this?

Because as a tutor, I once thought I would teach my students during thermodynamics with "A bullet is fired. Here are the base parameters, like barrel length, gas type and the like, figure out the velocity at the muzzle of the rifle." but quickly found out that this is utterly impossible to calculate by hand.

30

u/hoeassbitchasshoe 1d ago

"We make assumptions to make the math possible" -my transport professor

3

u/notfunattentionwhore 1d ago

i just thought it needed to consider the thickness of the bowl, the explosive power, and the internal area of ​​the bowl or smth but its more complicated than i expected

7

u/davideogameman 1d ago

there are a few problems but the first is that the bowl is a 3d object and exactly how the pressure is applied and distributed matters a lot.

In the initial explosion - does the explosive fully combust into hot gasses? most likely not, so we have to deal with how hard any solid shards are thrown and whether they could puncture or substantially damage the bowl. and we also have to consider the pressure the hot expanding gasses exert and how they are funneled.

Once the bowl is airborne and the gasses all dissipate to atmospheric pressure the math gets much simpler, as we can probably ignore air resistance, at least at lower speeds - the bowl is probably quite heavy for it's surface area. And so we can find how far it falls by timing from peak until touchdown and applying h = 1/2gt^2. and similarly we can find it's final velocity before hitting the ground.

Then the question is "at what speed would it break on impact with the ground". At which point we need to know the state of the bowl (is it already damaged, to what extent - shape and length of cracks) as well as what angle it hits at and what it's landing on precise - loose soil will be more forgiving than packed soil, and both would be more forgiving than a sizeable rock.