Why do clothes crumple when folded?
Show answer & explanation
Answer: Fiber stress creates creases
Gravity pulls on fabric folds — Wrong. Gravity can worsen creases, but crumpling occurs because folding stresses fibers beyond elastic limit, causing plastic deformation.
Material loses original shape — Wrong. Shape changes, but mechanism is fiber stress—bending creates compression (inside fold) and tension (outside), exceeding elastic limit.
Fiber stress creates creases ✓ — Correct! Fabric fibers bend when folded. Outside of bend: fibers stretch (tension). Inside: fibers compress. Elastic limit: maximum stress before permanent deformation. Sharp folds exceed elastic limit—fibers permanently deform (plastic deformation)—crease! Iron provides heat + pressure—relaxes fibers back toward original configuration. Wrinkle-resistant fabrics have elastic fibers or special weaves resisting plastic deformation. Cotton wrinkles easily; polyester resists.