[VAL] Boyles Law and Auto Racing.

["Ralph Wardlaw" <rwardla@xxxxxxxxxxx>]

I am not replying to any particular message here. I just think when the
subject turns to auto racing, many of you don't really understand the
problem. Let me point out a few things:

1. Auto race teams have at least one engineer on staff.
2. During a race, tire pressures are changed, individually, by as little as
1/2 psi cold pressure, to improve handling (cornering).
2. They conduct tire "tests" frequently at various tracks around the
country, at considerable expense.
3. There is always a tire engineer from the tire company present during
these tests. In the case of NASCAR, a GOODYEAR engineer.
4. They record data regarding the handling of the car versus tire pressure
on the four individual tires, and at the temperatures involved.
5.  As Susan pointed out, the pressure in a tire at constant volume and
temperature is the sum of the partial pressures of the gases involved, per
Boyles law.
6.  Now, would you rather deal with that data in terms of a dry, pure gas,
or in terms of whatever you air compressor inhaled from the local
environment, at whatever  temperature, humidity and altitude exists where
you happen to be located. A constant reference is better than a random
reference.

The answer is obvious. You use the constant reference.

The good Doctor stated that the only advantage is to the Nitrogen supplier.
Note that I have not infringed on his copyrighted material.

RW