Why is this car not going as fast as the driver would like? It is missing one essential thing.
Dear Dr. Boli: I understand the basic principles of internal-combustion engines: they operate by exploding, and as long as we pray hard enough, the explosions don’t kill us. I even have some acquaintance with electric motors, which operate by magic. But the thing I don’t understand is racing stripes. Whenever people want a car to go fast, they put racing stripes on it. They put racing stripes on racing cars. They put racing stripes on expensive sportscars, so that they can make it to the red light at the end of the Liberty Tubes before anybody else. Just this afternoon I saw racing stripes on a Honda Odyssey, and the woman who was driving it certainly acted as though she was on her way to a fire, or from a fire. So what is it about racing stripes, anyway? Do they really make cars go faster? —Sincerely, Bicycles Are a Mystery Too, but No One Wants to Talk About It.
Dear Sir or Madam: Racing stripes do indeed make cars go faster, but there is no mystery about it. It is simple physics. At high speeds, the single thing that retards the progress of a vehicle most is air resistance. Left to themselves, air molecules will just stand around in front of the car waiting to see what will happen. This creates resistance. It is desirable, therefore, to make the air less resistant, which is best done by making it move easily along the length of the car. Now, air molecules are simple souls, with a limited vocabulary, and it is not easy to make them understand us if we try to express what we want from them in complex sentences dripping with relative clauses. Yet they are not unwilling to please us—quite the contrary, in fact. What they need is for us to be simple and direct with them, and therefore visual communication is preferable to verbal. The racing stripes point the direction of desired air flow along the vehicle in a way that even the simplest air molecule can understand. Many mysteries have similarly simple explanations once you understand the physics of them. To balance a bicycle, however, requires divine intervention, which is a very complex subject indeed.