Why is rubber used to make cycle seats instead of wood or iron?

(N/A) Rubber is an elastomer,which means it can undergo large deformations and return to its original shape due to strong intermolecular restoring forces. When a bicycle passes over uneven ground,the seat material experiences stress and deforms,absorbing the energy of the shocks. Because of its elasticity,the rubber molecules return to their equilibrium positions once the force is removed,providing comfort. In contrast,wood and iron are rigid materials; they do not deform significantly under such loads,meaning they would transmit the shocks directly to the rider,causing discomfort.