sleepy wrote:
It turned out that up to 48 mph that the most energy used was to pull the load (weight) and above 48 mph it required more and more energy (Horse power) to push the wind (drag)
He says that I have stumbled on to a "constant"... that the switch in energy used from what is being "pulled" to what is being "pushed" through the wind on any vehicle happens at about 48 mph.
Sleepy
Interesting that you stumbled onto this as it should be fairly common knowledge. Even dummies like President Nixon knew this back in the 70's. This information was part of the basis for the national speed limit that was set at 55mph in an effort to reduce oil consumption during/after the 1970's oil crisis. Some states went further or already had lower speed limits. It was supposed to net a 2%+ reduction in oil consumption, but in reality it wasn't anywhere close to that.
It's also the same basic principle on why under about 50 mph you're better off with the windows open then using the A/C. And over that, the A/C is the better option to cool your car.
That was part of history and math classes in my day anyways.
later
C
