Why are car seat-belts designed to stretch somewhat in a collision ?

Why work is required to be done to stretch a wire?

Why are cars, aeroplanes and rockets streamlined ?

Why are the car lights dimmed when the starter is operated?

According to collision theory of reactions, Why all molecular collisions do not result in effective collision?

Why does rubber become stiff on stretching?

A car is moving with a velocity V. The car driver sees a truck at rest at a distance s. To avoid collision which is better, to apply brake or to turn sharply ?

The converyor belt is designed to transport packges of verious weights.Each 10 kg package has a coefficient of kinetic friction mu_(k) = 0.15 .If the speed of the conveyor belt is 5 m//s and then it suddenly stops, determine the distance the package will slide before coming to rest (g = 9.8 m//s^(2))

The converyor belt is designed to transport packges of verious weights.Each 10 kg package has a coefficient of kinetic friction mu_(k) = 0.15 .If the speed of the conveyor belt is 5 m//s and then it suddenly stops, determine the distance the package will slide before coming to rest (g = 9.8 m//s^(2))