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= __Physics of Car crashes with and without seatbelts __ =

All cars are created with crumple zones or impact release spots, thus making the force smaller due to the fact that the impact will slow down over a longer period of time, However, this alone does not save lives. The crumple zone only slows the car gradually. Theres only one way to slow the passengers more gradually is if they are attached to the car. Otherwise, the car may come to a stop more easily, but the people will to stop as soon as possible upon striking the already stopped inside of the car. the force is much larger due to the fact that they are stoped a lot faster. 

==== One of the only ways to greatly reduce injury and death is to wear your SEATBELT! Statistics show that 63% of people killed in accidents are not wearing a seatbelt. If 90 percent of Americans buckle up, we will prevent more than 5,500 deaths and 132,000 injuries annually. ==== ==== ﻿ ﻿**The Physics of wearing a seatbelt is shown by the picture to the upper right. When wearing a seatbelt your body is pushed into the chair becoming one with the car so you are not flying freely in the car. without a seatbelt your given force is multiplyed by 4. Seatbelts stop the majority of kinetic energy in your body**﻿ **when the vechile comes to a sudden stop.** ====

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=Protection by Seatbelts= These statistics come from Leonard Evans, "The Science of Traffic Safety" Here is a formula using force and seatbelts.
 * Vehicle || Occupant || Protection Device || Effectiveness in Preventing Fatalities ||
 * Car || Driver || Lap/ shoulder belt || 42 +/- 4% ||
 * Car || Right front passenger || Lap/ shoulder belt || 39 +/- 4% ||
 * Car || Left rear passenger || Lap belt || 19 +/- 10% ||
 * Car || Right rear passenger || Lap belt || 17 +/- 9% ||

Source:[]

Not wearing a seatbelt the driver will fly free in the car until stopped suddenly by hitting the steering wheel, dash, windshield The stopping distance is estimated to be about 1/5 of that with a seatbelt. The amount of energyit takes to stop the driver is equal to the average impact force on the driver times the distance traveled in stopping. A crash which suddenly stops the car and driver takes away all its kinetic energy, and the shorter stopping distance dictates the amount of force.



Source:http://hyperphysics.phy-astr.gsu.edu/hbase/seatb.html





So use your mind, soul and body and wear a SEATBELT! (heres a video to show you crashes with and without seatbelts) .media type="custom" key="8416104" Sources: