Sunday, June 17, 2007 Updated: June 20, 7:37 PM ET
Hit the pedal with some fundamental physics
By Bill Borden Special to ESPN.com
The principles of racing (as in all sports) are rooted in the laws of physics. For example, Newton's first law of motion is: "An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and direction unless acted upon by an unbalanced force." Tony Stewart slides up the track and hits the wall in turn two! Or, "An object in motion tends to stay in motion with the same speed and direction -- unless" ... Upon replay we see that Jimmie Johnson (an unbalanced force) just barely touched (acted upon) the rear quarter panel of Tony's car causing Tony to lose control and hit the wall. See, it is a simple physics equation.
Elliott Sadler's No. 19 car and and Denny Hamlin's car exhibit the laws of physics, and a lot of friction, on the last lap of the Budweiser Shootout in February.
His second law of motion is: "The acceleration of an object (In this case Tony Stewart's left arm extended out the driver's window telling Jimmie he is No. 1 in his book) is dependent upon two variables -- the net force acting upon the object and the mass of the object." These laws and others such as "Every action has an equal and opposite reaction," are laws that the racer must understand and manage successfully if he is to be competitive on a consistent basis.
He needs to understand and apply the actions and interactions of lateral force, torque, friction, geometry, mathematics and the many other forces of nature that come into play. Pretty boring stuff but absolutely necessary for him to understand if he is to set up his race car correctly and drive it confidently and competitively.
The most important factor to a driver is one you seldom hear the announcers talk about. It is "Confidence." Confidence in his equipment that it will do the same thing (or close to it) every time he turns the steering wheel or applies the brakes, etc. Knowing what reaction he can expect builds confidence in the driver. If he is confident in himself and his equipment then he will most likely be competitive on the track.
The next time you see a driver make what appears to be a daring move on the track and you exclaim to yourself "How did he do that?!" think about the confidence he had to have to pull it off. If he understands the laws of physics and plays within the rules of nature then he can do seemingly impossible things as long as he does not violate any of those laws.
Most of us watch Nextel Cup racing for the excitement of seeing 3,300-pound race cars charging side-by-side around a track at speeds we can only dream about ever experiencing ourselves. All those roaring engines and the fast-paced action get the adrenalin pumping through our veins as we cheer for our favorite driver.
The average race fan would never ever be caught dead attending a boring ballet -- right? Wrong! When you are sitting in the stands at the track or relaxing in front of the TV at home you are watching the ultimate ballet unfold before you out there on that track. Physics dictate that it be that way. Racing is much more like ballet than football. Remember "equal and opposite"? Two football linemen will crash into each other at the line of scrimmage in an attempt to move the other backward. That is physics in its rawest form but it is not the physics of racing. The ballet dancer leaping into the air and performing a graceful pirouette is more comparable to the physics involved in racing.
Mashing the throttle and throwing a car sideways into a corner while bouncing off a competitor may be thrilling and exciting to do and to watch but it has a short life span on a race track. It is not racing to the purist. Watching two competitors race side-by-side while matching their skill and determination in graceful harmony for lap after lap as they dance on the ragged edge of disaster is what racing is about to the purist. It demands a driver's full concentration, complete confidence and careful consideration for the laws of physics if he hopes to win.
Detractors of the sport claim that race car drivers aren't really athletes because all they do is sit and turn a steering wheel. That's like saying all a quarterback does is step back and throw passes, or all a center does is reach up and block shots. The extraordinary discipline and ability to totally concentrate for extended periods of time (sometimes hours) and to have the coordination, control and lightning-quick reflexes required to drive a race car at competitive speeds in temperatures that can reach as high as 140 degrees inside the cars make race car drivers athletes in my book.
The average hourlong professional football game has just 11 minutes of physical action during the entire game. If you play only defense or offense then you will only have about five to six minutes of total action per game. That computes to only about 10 percent of the total game that a football player is physically active. Compare that to the Coca-Cola 600 coming up this weekend at Lowe's Motor Speedway that can take up to six hours to complete and you can, hopefully, see my point.
Remember centrifugal force from high school science class? How many remember centripetal force which is centrifugal's equal and opposite? And what does it have to do with driving a race car? When the driver enters the corner and turns the steering wheel he is creating centripetal force (remember Newton's first law of motion and the law of equal and opposite?) And, depending upon how much centripetal force he is creating by turning the wheel, he is causing an equal and opposite amount of centrifugal force that wants to push the car out to the wall.
Plus, when he applies the brakes as he enters the corner he is invoking Newton's second law of motion along with creating friction in the tires and brakes, torque, yaw and lateral force in the chassis, altering inertia, causing dynamic load transfer, changing aerodynamic downforce and a dozen other things I cannot recall at this moment. And, if he is a "football player," he hits the wall somewhere past the center point of the turn's apex. But, if he smoothly grooves on through the corner then he mastered his pas glissé in ballet class. Put that in your dunk shot and smoke it, Shaq!
And all he did was turn the wheel and step on the brake! Heck, I do that every time I drive my car. Of course, I don't do it at the speeds the Nextel Cup drivers do. And, I may not apex the corner as well as they can lap after lap. And, I don't normally do it while driving five or six inches off the bumper of the guy in front of me or within inches of the guy running beside me or maybe even both while traveling the length of a football field per second and listening to my spotter telling me I'm clear low or having my crew chief shouting in my ear that a higher entry will change my apex thus improving the front end geometry while reducing or modifying my dynamic load transfer, friction, torque, yaw and all those other things I couldn't recall in the paragraph above. And, oh-by-the-way, what are your gauges reading since NASCAR won't let us have on-board telemetry for that information.
It is a wonder to me how Tony Stewart ever finds the time to flip off his fellow competitors while passing them in the corners! He must have gotten a "A" in physics.
Racing, like no other sport, is a unique and interesting blend of individual performance supported by a team effort. It is a marriage of art and science. It is a continual stream of contradictions. It is an endless craps game where hard work, dedication and preparation can improve your odds but Lady Luck may never call your name. It can be tedious, frustrating and exasperating. Nobody, in his right mind, should subject himself to such physical and emotional punishment. I love it. Where's a helmet?! I see Tony coming off turn four!
Bill Borden is a former championship winning crew chief who operated David Pearson's Racing School for many years.