The term "Low Velocity" collisions refers to the relative speeds most often seen in motor vehicle accidents (MVA) and falling accidents.
There are three collisions that occur during a single MVA. All of them are due to Newton's first law of motion and conservation of energy and momentum.
| First there is the collision
between
the moving vehicle and something that is not |
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Then there is the collision of
the passenger with the inside of the vehicle |
| Finally there's the collision between a
persons innards with their rigid body When the head is hit and the brain
rocks
back and fourth it is called coup counter-coup |
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| There are many
similarities between falling injuries and MVA injuries. In both cases energy is being transferred from one body to another, but in the case of someone falling their potential energy is being turned into kinetic energy. |
PE=mgH KE=1/2mv^2 |
| Since energy is always
conserved we can say that all of a persons potential energy is transferred into kinetic energy upon impact. |
PEi+KEi=PEf+KEf |
| Conservation
of energy in a low velocity collision against something that is not sharp causes blunt farce trauma. Abrasions are a sign of blunt force trauma that has had a long contact time. |
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When there
is a lot of energy transferred there is potential for very serious
injuries. These injuries can very often be permanent brain injury. |