Asuref n tiddi

Amodel-agi (3D) ibeyyen amgired n usuref n tiddi s yiwet s yiwet. Yebda si 1 cm, yettali s tuzzma n 10 seg decimètres alamma yewweḍ ɣer 1 m, syen yesseɣli-d tanzagt n 1 cm ɣer 1 mm. Isfeham acuɣer yal taɣawsa n tiddi tesɛa yiwet n tigejdit deg uskasi n usuref.