Dumping+Over+an+Overpass+(By+Andrew+Smith)


 * Description : **** dumping over overpasses is an extremely dangerous activity. Some do it for fun, others do it to get ride of unwanted objects, and sometimes they are accidents. All cases are equally as dangerous and drivers should all be well aware of the damages that could accrue. Even pumpkins can smash windshields open, it doesn’t take a huge rock. **

· All objects thrown have the potential to cause an accident, even small harmless objects could cause motorists to slam on their breaks. · Overpasses created to help regulate the amount of deer/wildlife on the road. Helps prevent crashes. · There were approximately 1.5 million deer-vehicle collisions across the nation in 2002, resulting in an estimated 150 human deaths, 1.5 million deer deaths and $1.1 billion in vehicle damage.
 * Statistics or News Articles **–

Acceleration of both the dropping object and the car are important to understand so that we can masseur the force at which the objects collide and so we can say when they will collide
 * How the Kinematics (principles of motion) Relate to This Hazard **

the above image is a picture of an overpass. in a normal situation you would have lots of cars passing underneath and in some cases overhead as well. overpasses are generally placed on highways, and so the cars going under them are usually traveling at a high rate of speed, and if not then its probably a traffic jam. in our part of the united states the most common speed limit is 65MPH, or 29 meters per sec. the height of most overpasses are 14 feet (4.26 meters )in urban areas unless specified from a sign.
 * Example Scenario **

now say your driving towards an overpass on the highway going 29 meters per second, assuming you go speed limit, and you see in the distance something on top of the overpass. you need to ask yourself what are the safe ways to approach this problem and this is where a mixture of kinematics and common sense comes in to play. the acceleration of your car, the velocity and the distance are all important factors, as well as what happened on the overpass and if something is dropped how long it will take for that object to fall. if we are assuming that the overpass is normal height which is 14 feet the object will fall fast. Shown here by a chart made by NASA in fact it will take less then a second to actually hit the ground. Now this means two things. One it is very unlikely that you will actually be hit by this object and two you have very little time to react to the fallen object. if your going 29 meters per second that means that if your 29 meters away from the overpass as the object is dropped, you will be hit, and you wont be able to stop fast enough to avoid the collision. the human reaction time is about half a second and that only give you another half a second to stop. Now some graphs As shown in this graph the small line is the line of the object that is falling and the point A is when the object hits the ground as you can see if the object is thrown when the car is relatively close then the object will not even come close to hitting the car. However this may cause motorist to slam on their breaks and therefore cause an accident

now in this graph the car starting point is at -29 meters so that means the car is 29 meters away from the overpass, if the object is dropped when the car is at this distance and the car is going 29 meters per second then the car will probably get hit by the object there is a little space because the object has yet to hit the ground but the graph does not take in the fact that the car windshield is off the ground. in any case if the object hits the car or not, it will be on the road and so if the object is big the motorist will collide with it, and if not then they still may apply the breaks.


 * How this Hazard Can Be Avoided With a Better Knowledge of Kinematics **
 * knowing this data does little to help avoid the possible accidents that could happen, there would be very little time to react, and slamming on the breaks can cause a more dangerous situation, as far as avoiding this situation goes, it is extremely difficult. **

Because there is not much you can do to avoid this hazard instead, I will end by saying the things that you should not do. First never slam on your breaks, no matter what is being thrown. This can lead to accidents, don’t ever speed up because that will just increase the force at which you get hit by the object, if anything slowly slow down, but be careful of this too, this may make it easier to get hit. If you are in a traffic jam and you see someone dumping over an overpass pull over and call 911, don’t go under the overpass because you would be stuck there if they decided to throw something. And last if multiple items are being thrown the chances of being hit are increased, however there is still little you can do about the situation, if you think you can slow down and pull over before you reach the overpass then do so, otherwise proceed with caution, for more information on collisions and how to avoid them see the Collisions page
 * Conclusion **


 * Citations**

Gibbons, Jim (2009) Nevada Department of Transportation, safety overpass. Retrieved from []