Kinetic energy increases with the square of the velocity, so in a head-on collision everything not buckled on the back seat becomes a missile heading towards th

Kinetic energy increases with the square of the velocity, so in a head-on collision everything not buckled on the back seat becomes a missile heading towards the passenger seats. Even a bag with a laptop is dangerous and you should put it in the foot compartment. And that's like 3kg while an average person will weigh around 70kg.