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by telchar 1346 days ago
You lost a zero in there, so more like 146km.
3 comments

Not enough for a space elevator on Earth, but definitely in the range you need for very long suspension bridges -- think in terms of railway bridges over the English Channel, the Straits of Gibraltar, the Irish Sea, and (with causeways/island hopping) the Bering Straits.
Examples here, one can sort by breaking length: https://en.wikipedia.org/wiki/Specific_strength

(2 GPa) / (1400 kg/m^3 x 10 m/s^2) = (2e9 N/m^2)/(1.4e4 N/m^3) = (2e5/1.4) m = 140 000 m = 140 km

P = F/A, F = M x g, M = A x L x rho

L = M/(A x rho) = (F/g)/(A x rho) = (F/A)/(g x rho) = P / (g x rho)

Oops, tx. Seemed low.