Geared Way, Way Down
A Parable of Efficiency
  

Did you ever think about the way gear ratios, like interest rates, can get out of hand? You could build a car geared so low it would not get across the road in a lifetime.
  

Here is how it works: if we take a set of gears that provide a five to one reduction, the automobile's engine will have to turn five times before the driveshaft turns once. Nothing unusual there, but let's put fifteen of these gear sets one behind the other until we fill up the space between the engine and the rear axle. Any good machine shop can do it. The gear reduction with all fifteen transmissions in low gear will be about thirty billion to one.
  

Now let's start the engine and let it run at 3,000 revolutions per minute. Drop all of our little transmissions in low gear and let out the clutch. Our engine will have to run for nineteen years and four months to turn the shaft once.

Assuming a four to one ratio in the car's rear axle, we will wait for more than 77 years for the wheels to turn once.

Let's keep this a secret among ourselves. Somebody might make it into a government project with ten distinguished scientists, five hundred employees, and a budget of twelve million dollars.

© 1997 Wilfred R. Franson