Why Safety Belts - Audi A7 Sportback 2015 Owner's Manual

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- Failure to pay attention to the warning
light that come on, could lead to person-
al injury.
Why safety belts?
Frontal collisions and the law of physics
Frontal crashes create very strong forces for
people riding in vehicles .
Fig. 15 1 Unbe lted occupants in a vehicle head ing for a
wall
Fig. 152 The vehicle cras hes into the wall
The physical principles are simple. Both the
veh icle and the passengers possess energy
which varies with veh icle speed and body
weight . Engineers call this energy "kinetic en-
e rgy."
The higher the speed of the vehicle and the
greater the vehicle's weight, the more energy
that has to be "absorbed" in the crash .
Vehicle speed is the most significant factor. If
the speed doubles from 15 to 30 mph (25 to
50 km/h), the ene rgy increases 4 t imes!
Because the passengers of th is veh icle are not
using safety belts
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fig. 151, they will keep
moving at the same speed the vehicle was
moving just befo re the crash, unt il something
stops them - here, the wall ¢ fig. 152.
Safety belts 139
The same principles apply to people s itting in
a vehicle that is involved in a frontal coll ision .
Even at city speeds of 20 to 30 mph (30 to 50
km/h), the forces acting on the body can
reach one ton (2,000 lbs, or 1,000 kg) or
more . At greater speeds, these fo rces are even
highe r.
Peop le who do not use safety belts are also
not attached to their vehicle . In a frontal colli-
s ion they will also keep moving forward at the
speed their veh icle was travel ling just before
the crash . Of course, the laws of physics don't
just app ly to frontal collisions, t hey determine
what happens in all kinds of accident s and col-
lis ions.
What happens to occupants not wearing
safety belts?
In crashes unbelted occupants cannot stop
themselves from flying forward and being in-
jured or killed. Always wear your safety belts!
Fig. 1 53 A driver not wearing a safety be lt is violently
th rown forwa rd
Fig. 154 A rear passenger not wearing a sa fety belt
will fly forward a nd strike the driver
Unbelted occupants a re not able to resist t he
tremendous forces of impact by hold ing tight
o r bracing themse lves. Without the benefit of
safety restraint systems, the unrestra ined .,..