I would like to expand my remedial teaching blogs to include a lesson in practical physics. Specifically, the laws of physics that pertain to something we all do every day, drive a car. I have 44 years of driving experience and more than a million miles to base my thesis on so please pay attention, this blog might save your life. I believe we would all be much safer drivers if we made the effort to understand the physics of objects in motion.
Let’s begin with a few simple measurements to provide a baseline for comparison. On average, cars can weigh up to 5000 lbs. but for the sake of simple problem solving let’s use the low-end of 2000 lbs. Now let’s look at speed. A car travelling at 60 miles per hour covers a distance of 88 feet every second. The average car is less than 20 feet long but let’s use that length anyway because it’s easy to apply. Now let’s think about reaction time and stopping distance. Reaction time is the time it takes each driver to realize there is danger ahead and hit the brakes. At 60 mph, an optimal reaction time of 1 sec. would mean that the car travels 88 feet while we’re processing that information. That’s four car lengths before we even start braking. When we include reaction time with average braking distance we find that a car needs 240 feet to stop at 60 mph. That is 12 car lengths. For the lucky few who can afford a Porsche, we could probably knock off 60 feet but it would still be 9 car lengths. With the added time caused by distracted driving (texting, screaming kids, coffee drinking, make-up re-touching etc.) some drivers never even hit the brakes.
Now let’s think about the force generated by a 2000 lb. vehicle hitting another vehicle at 30 miles per hour after we have tried to brake. The math is simple. Weight times speed equals force or in this case 30 x 2000 = 60,000 lbs. of energy that needs to be redistributed somewhere else and that means you are going to meet your airbag for the first time. There are three collisions in every accident. The car impacts with another object, the occupant impacts with the interior of the car and then the internal organs impact with the skeleton of the occupant. Let’s say your heart weighs a pound. At 30 mph your heart now has a force of 30 pounds as it collides with your rib cage. The same thing happens with the brain as it hits the bones of the skull. Just for comparison, 30 mph is faster than any human can run, so just imagine yourself running as fast as you can right into a wall. How much damage to your body would that cause? That’s nothing compared to a car accident with broken glass and sharp metal.
Now ask yourself this question, how many times have you driven at 60 mph with less than 12 car lengths between you and the car ahead? I would bet the answer is always, because I’m guilty too. So, if nature’s laws have no exceptions, aren’t we all at huge risk? Some of you are now trying to make yourselves feel better about your chances by thinking about all the safety features on that expensive car you drive. Good for you but what about the poor guy who can’t afford a BMW but because he stopped in time and you were busy on your phone and your reaction time was more like 3 seconds instead of 1, you just slammed into him from behind at 60 mph. You probably walked away but he might be dead.
Guess what other laws have no exceptions? That’s right, you just committed involuntary manslaughter and even though you walked away from the accident, you get to spend the next year in prison. What, you didn’t know you can go to jail for causing a fatality in an accident? Sorry, but that’s a law too and only a really expensive attorney is going to get you off with a suspended sentence. And if that attorney is really good, you will probably want to retain him to fight the civil lawsuit filed by the dead guy’s family and their attorney will be really good at collecting a huge judgment against you because he’s going to get about 40% of every dime he can squeeze out of you in the settlement. And you will settle out of court because the last thing you want is the cost of a trial on top of the inevitable settlement. Would you like to hear about bankruptcy laws now? I thought not.
So, at the end of the day, we have the realization that driving too fast, not allowing enough space between cars to stop safely, driving while distracted or intoxicated and refusing to accept the absolute laws of nature, will inevitably end up with pain and suffering on an unimaginable scale, but so what……. “It will never happen to me because I’m a good driver.”
Do you really want to bet everything on that premise?
(Editor’s Note. On average, about 92 people are killed in traffic accidents each day in the United States. Driver error is the primary cause. Please be a safe driver, not a statistic.)
©Guy R. Horst and grhgraph.wordpress.com, 2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Guy R. Horst and grhgraph.wordpress.com with appropriate and specific direction to the original content.