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EXTRACT E.

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Part C: The nature of the "whiplash mechanism".

Chapter C.1 How does such a mechanism affect a body inside the struck car?

1. In general.

A logic connection between where injuries of the body might occur and the way the damage mechanism has affected the body.

I did in 1991 and 1993 make two papers in Norwegian describing how and where the loads caused by the "whiplash mechanism" in a rear-end collision might affect a body. In the last of these descriptions I found it necessary to describe how such loads, affecting the body with very high loads acting in extremely short periods of time almost like explosions, causing very rapid changes of the velocity might affect even cells and their structures.

The study of how the human body responds to the mechanical exposures of the "Whiplash" mechanism must be left to the medical experts knowing the properties of the organic materials and with knowledge to consider the effects of the affecting loads.

When I describe the effects I am not making a description of injuries, only of the mechanical deformations to organic structures of different kinds. The physiologic structures of a body will of course derive in a very high degree from the structures in even the most complex mechanical construction, involving live fibers of different kinds and with different mechanical properties. Looking closely at a small section of the body I will find elements of different mechanical properties, different length and different square sections. What's to be considered as a lasting deformation to the structures from a mechanical point of view is to be considered together with the period of time the structures need to restore it's structure. Any deformation of structures which do not return to their initial condition as the pressure is released are to be considered as lasting deformations.

Looking at a live body affected by forces in an impact, where the elastic abilities of the structures are a determent factor of the change of velocities during the impacts, I have to make up my mind what to be considered as a lasting deformation and what to be considered as a deformation giving a further acceleration during the period of expansion. Studying the physiologic abilities of different kinds of structures, it seems to be some kind of fibers which may stand a static or slow changing load well, even if it is to be considered as high, but exposed to a rapid change and even at smaller load, this may give deformations, ruptures and changes in the structure changing the mechanical abilities.

Any lasting change of a structure makes a difference in the kinetic energy between the start and the end of a movement. This might be visible deformations caused by stretches, shifting and compression, and it might be damages only visible by using microscopes, advanced examination apparatus and I think even surgical methods. As the human body is a live structure with the opportunity of self restoration of wounded elements of most structures, and with the possibility of dying of other cell structures when damaged, the time when the examination is carried out seams to be an important factor when examining the different elements of the body to find visible organic changes.

Considering the body as a mechanical structure, I will define an elastic structure to be a structure which immediately restores it's structure as the loads are released affecting the body with an accelerating force during the expansion. Any healing and restoring of structures not immediate as the loads are released or without making any accelerating force during the expansion are from a mechanical point of view to be considered as a permanent deformation. In this matter, considering possible effects of the "whiplash mechanism" in a rear end collision involving the head and the neck region as well as the whole spine, the possibility of symptoms involving other parts of the body, not directly affected by the acting loads must be expected. These are questions to be answered by medical experts, not by a technician with some medical knowledge. A co-operation across professional boarders will be welcomed.

2. Affected areas due to the energies involved.

I should have made clear that it is not a direct proportionality between the strength of an impact and the acting forces neither towards the car nor affecting the persons within the car. Depending on the stiffness of the affected structures even a low velocity impact may cause very high acting forces.

What's to be noticed is the relation between low velocities and low changes in energy. The kinetic energy of a moving object will be increased 4 times when the velocity of the object is increased twice. All work executed in an impact are done by the energy released when the velocity of the striking object is reduced. The acting forces affecting a body or more actual between parts of the body, may be equal in two collisions at different velocities, but the region within the affected structures may be found might be much wider in the strongest collision.

As the strength of collision increase, the areas affected by the loads onto the body will increase both in width and depth. As a consequence also heavier parts of the body will get a relative velocity, different of the velocity of the car or other parts of the body, giving a different movements, affecting other parts of the body.

For the Next page. Part C continuous.

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