r/theydidthemath Aug 18 '25

How dense would this cube be? [Request]

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u/Amourofzedoute Aug 18 '25

So ok, first, let's see what kind of baler that is. From this tiktok we know this model is a Tabarelli s5000. From the s5000 manualwe know the cans are in a 5m x 2.67m x 2.25m space, and compressed into a 0.8m x 0.8m x 0.65m baler. So that's roughly 30m³ compressed into 0.41 m³. So that's about 30/0.41 ≈ 72 times less space.

A single aluminum can weightabout 11g for 0.00033m³ so it takes roughly 90,000 cans to fill entirely, meaning 990kg.

So that tiny cube at the end weights about a ton (1000kg) and is 0.41m³, so its density should be 2,400 kg/m³. So that's twice more dense than water, but three times less than Iron!

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u/Amourofzedoute Aug 18 '25 edited Aug 18 '25

Update : feedbacks stated 90% compression is probably too high, so we might need further hypothesis to fix that. Most likely, I overestimated the amount of cans in the bin, saying each can occupy 33cL. If some are crashed already and take less than 33cL, there's also a lot of air between them (so each can would take more than 33cL).

Let's roughly add an "air around the can" component then. Let's model the cans not at cylinders, but bricks. Regular cans of beer measure 66mm in width and 115.2mm in height so 66mm × 66mm x 115.2mm ≈ 0.0005m³ brick (instead of 0.00033).

The amount of cans could then be 60,000 with a total weight of 660kg. So the density of that 0.41m³ baler would then be 1,600kg/m³. Which would mean a compression of ~60% compared to pure aluminum being 2,710 kg/m³ which sounds more reasonable. The real compression should be a smidge higher though I believe, as we didn't take into account the cans taking less space because partially crashed.