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0 pointsdghughes7y ago0 comments

And if the foam cells have a vacuum in them (in? lack of?) how does it not implode when on earth.

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The difference between Vacumn and 1atm is 14psi, bike tires pumped to between 50-120psi (on my road bike for example), 14 psi isn't that large a pressure for a reasonably strong/stiff material.

dghughesOP7y ago

I know what you mean but in a way I think there is a difference since the material has to withstand inward pressure; compressive forces.

A tire/tyre rubber has tensile strength, most (all?) pressure vessels on earth are tensile. It seems odd the difference between compression and tension when it comes to certain forces.

Anyway, I just though it would matter.

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noir_lord7y ago

The difference between Vacumn and 1atm is 14psi, bike tires pumped to between 50-120psi (on my road bike for example), 14 psi isn't that large a pressure for a reasonably strong/stiff material.

dghughesOP7y ago

I know what you mean but in a way I think there is a difference since the material has to withstand inward pressure; compressive forces.

A tire/tyre rubber has tensile strength, most (all?) pressure vessels on earth are tensile. It seems odd the difference between compression and tension when it comes to certain forces.

Anyway, I just though it would matter.

j / k navigate · click thread line to collapse