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Dispelling the Haze: Crashes and Crime. A Presentation of Facts and Informational Mathematics by the Ohio State Highway Patrol. Presentation Prepared by: Tpr. John C. Thorne III M.S. Goals of Instruction. To dispel myths about the nature and dangers of crime
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Dispelling the Haze: Crashes and Crime A Presentation of Facts and Informational Mathematics by the Ohio State Highway Patrol
Goals of Instruction • To dispel myths about the nature and dangers of crime • To educate young adults on the real and potential consequences of unsafe driving • To change unsafe driving habits through education of physical laws of vehicle behavior.
Comparing Crime and Crashes: What Should I Really be Afraid of?
2005 Uniform Crime Reports: FBI Nationwide Crime Statistics • 16,692 Murders • 93,934 Rapes • 417,122 Robberies • 862,947 Aggravated Assaults
2005 UCR Crime Statistics: Ohio • 585 Murders • 4,557 Rapes • 18,696 Robberies • 16,435 Aggravated Assaults
2005 UCR Crime Statistics: Clermont County Sheriff • 0 Murders • 45 Rapes • 12 Robberies • 15 Aggravated Assaults
Union Twp. 0 Murders 2 Rapes 22 Robberies 5 Aggravated Assaults Pierce Twp. 0 Murders 7 Rapes 4 Robberies 5 Aggravated Assaults 2004 UCR Crime Statistics: Clermont Agencies
Miami Twp. 0 Murders 9 Rapes 8 Robberies 17 Aggravated Assaults Goshen Twp. 0 Murders 1 Rape 6 Robberies 25 Aggravated Assaults 2005 UCR Crime Statistics: Clermont Agencies Contd.
2005 National Highway Traffic Safety Administration Crash Data • 6,159,000 estimated total traffic crashes • 2,699,000 estimated total number of persons injured from traffic crashes • 43,443 persons killed from traffic crashes
2005 Traffic Crash Data: State of Ohio • 358,127 total traffic crashes • 131,245 persons injured as the result of a traffic crash • 1,326 persons killed as the result of a traffic crash
YOU DO THE MATH Nationwide 16,692 Murders 43,443 Traffic Deaths 585 Murders 1,326 Traffic Deaths Ohio
2005 Data: • The Cincinnati Metropolitan Reporting area to the UCR reported 115 murders in 2005 • This area includes 3 counties in Indiana., 7 counties in Kentucky., and 5 counties in Ohio in addition to the cities of Middletown and Cincinnati • The population of this area is over 2 million people
2005 Traffic Deaths in Clermont County • 28 people died on the roadways in Clermont County • 7 were ages 16-24 • 4 died on SR 125 between Amelia and Bethel • 16 people died because they were not wearing a seat belt
The Basics… • Before we start to talk about speed, crashes, and seat belts, we need to understand basic physics principles. • Newton’s laws of motion
Newton’s First Law of Motion • A body at rest tends to remain at rest, while a body in motion tends to remain in motion in a straight line, unless acted upon by an unbalanced external force • Simply put – an object in motion stays in motion until something causes it to stop
Friction • Friction is a force • There are two types of friction • Static Friction • Dynamic Friction
Friction • Static friction • The weight of an object pressing down on the surface of the earth creates this • To initially get the object moving, this force must be overcome • The initial static friction to get an object moving will always be greater than the dynamic friction generated between the object and the surface it is moving over
Friction • Dynamic friction • The friction encountered by an object moving over a surface • Varies based upon both the characteristics of the object and the characteristics of the surface • Expressed in “g” forces or percentages of the force of gravity • If the force required to move a 40lb. weight across a surface is 30 lbs., the surface can be assumed to have a dynamic friction, or “drag factor” of .75 “g’s” • The higher the drag factor, the quicker an object will slow to a stop on that surface
Newton’s First Law of Motion • Friction is a natural and omnipresent force that is acting on moving objects • Without friction, there would be no way to stop objects moving about • Objects on earth do not keep moving once they are accelerated due to the force of friction
What do these laws have to do with me driving my car? How does my vehicle behave…normally?
Vehicle Behavior • Your car, you, and everything inside of your car are bound by Newton’s Laws of Motion • It is because you and your car are bound by these laws that traffic crashes and fatalities are a reality • By understanding these laws and why crashes happen, you may be able to avoid being involved in a crash
Pre-Crash Factors • Speed • Following distance • Road and weather conditions • Attention span
Speed • One of the primary causes for motor vehicle crashes and fatalities • Perhaps the most widely known function of a police officer is to enforce speed laws • Why speed limits are in place and why they are enforced is based partially on Newton’s Laws of Motion
Speed • Most people measure the speed of their vehicle in Miles per Hour, but have no real concept of how fast they are truly traveling • A mile is a lengthy distance that we do not readily view on a daily basis • A better way to gauge the speed you are traveling on the road is by converting miles per hour into feet per second
Speed • To convert miles per hour into feet per second, multiply the speed in MPH by 1.466 • The result will indicate your speed in feet per second (FPS)
Speed • When examining speed in feet/second the actual distance you are traveling becomes more tangible as well as the time it takes you to cover that distance • This is especially useful when examining following distance and assured clear distance crashes
Speed • A demonstration • In the time it took this to appear, if you were traveling at 35 mph you would have traveled roughly the distance of a football field • At 85 mph, you would have completed a 200 meter sprint with about 1 second to spare
Following too Close • “Tailgating” or trying to “push” someone to go faster by riding close to the bumper of another car • Combined with excessive or unsafe speed is the major causative factor for vehicle crashes • You can and will be written tickets for following too close!!!
Following too Close • It is common to see vehicles following each other at a distance of 1-2 vehicle lengths (approx. 8-16 feet) while traveling at 65 mph • Could this be a major problem?
Following too Close • Human physiological studies indicate an average perception reaction time of a human being at 1.5 seconds • This reaction time is the amount of time that it takes the human brain to recognize a stimulus and respond to it
Driver Attention • How often are you really paying full attention to the road? • Are you – • Talking on a phone? • Playing the radio? • Talking to a passenger? • Thinking about American Idol?
Road and Weather Conditions • Speed limits are designed for maximum speed on a road for ideal conditions • Rain, snow, and ice affect the dynamic frictional value of a roadway (drag factor) • Reason for more crashes during these periods is driving behavior is not adjusted
Putting it Together • Because your vehicle adheres to the laws of physics, we can determine how it will behave by using mathematics • Primarily we can determine • Time needed to stop • Distance needed to stop • The amount of distance covered over a given time
Putting it Together • Equation for determining slide to stop: • Distance to stop = Speed (squared)/30 x drag factor of roadway • D = (s)(s)÷ 30f
Putting it Together • Increases in speed increase distance needed to stop • Decreases in drag factor of roadway also increase distance to stop (rain, ice, gravel, etc.) • What happens when you figure in response time?
Putting it Together • Convert your speed to ft/sec. (MPH x 1.466) • Multiply ft/sec. by average response – reaction time (1.5 seconds) • Add product to already determined slide to stop distance
Putting it Together • Does 5 mph over the limit really matter? • Do the math! • 55 mph or 60 mph on a dry road • 55 mph slide to stop = 144 ft. • 60 mph slide to stop = 171 ft. • Difference = 27 ft. to slide to stop
Putting it Together • When you enter your car and begin to travel, you are bound by Newton’s laws of motion • When your speedometer reads 65 mph (95.29 ft/sec), the vehicle and everything inside of it is traveling at that speed • It does not seem that way because your speed is uniform and relative to your immediate surroundings
Putting it Together • Because of Newton’s First Law of Motion, there are three impacts in every crash! • Vehicle vs. vehicle • Human vs. inside of vehicle • Human organs vs. human body • It is usually the third impact that is fatal!