Step 1: Define fabric stiffness testing. Fabric stiffness (also known as bending rigidity) measures a fabric's resistance to bending. Different testing methods are appropriate for various fabric types.
Step 2: Describe the "Heart Loop Test". This test involves forming a fabric strip into a heart-shaped loop, which is then hung. The loop's length is measured. Stiffer fabrics create shorter, wider loops. Conversely, flexible fabrics form long, narrow loops.
Step 3: Match the method to the fabric type. The Cantilever test is the standard for most fabrics. However, the Cantilever test is not sensitive enough for very soft, flexible, and drapeable fabrics. The Heart Loop test is better suited for these "limpy" fabrics as it is more sensitive to small stiffness variations in the lower range.
Conclusion: The Heart Loop test is ideal for measuring the stiffness of very flexible and limpy fabrics.
Match Fibre with Application.\[\begin{array}{|l|l|} \hline \textbf{LIST I} & \textbf{LIST II} \\ \textbf{Fibre} & \textbf{Application} \\ \hline \hline \text{A. Silk fibre} & \text{I. Fire retardant} \\ \hline \text{B. Wool fibre} & \text{II. Directional lustre} \\ \hline \text{C. Nomex fibre} & \text{III. Bulletproof} \\ \hline \text{D. Kevlar fibre} & \text{IV. Thermal insulation} \\ \hline \end{array}\]