4.9—Core Practical 8 - tensile strength of plant fibres

Tensile strength is the maximum load a fibre carries before it breaks. To compare plant fibres, attach a fibre securely, add weights one at a time and record the breaking load.

Keep fibre length, width, moisture and loading method as constant as possible. Repeat with several fibres of the same type, calculate a mean and report variation; a single break is not a reliable material comparison.

If three equal-length fibres break at different loads, the mean breaking load estimates typical strength while the spread shows how consistent the material is. A rope’s performance depends on more than one strand.

Breaking load is not automatically tensile stress: stress also depends on cross-sectional area. Do not compare fibres of very different thicknesses as if load alone measured an intrinsic property.