Which effect limited Roman ballista projectile range as wood dryness changed seasonally?

💡 Explanation

When wood dries, the mechanical properties change causing creep and relaxation affecting preload, because wood cell walls are hygroscopic. This decreases bowstring restoring force reducing energy delivery from the twisted ropes to projectile. Therefore preload force decreases rather than shear stress, trajectory, or density which are less directly linked to changes in wood dryness alone on the ballista.

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