Tarkin75 wrote:
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
When I was in the first grade '34 fords were common... my dad had a 1940 Studebaker (it seems that they tore the engine down a couple of times a year for valve jobs... spark plugs and tires didn't last very long... maybe they never got past 48 mph.
WWII started after I was born and I was in grade school the year when the war ended. NO one got a new car during the war... gasoline was tightly rationed, no Tires for the masses... all manufactured goods, along with food were rationed... people even saved the tin foil from a stick of chewing gum for the war effort.
As the economy improved after the war no one cared about fuel economy... fuel of all kinds was abundant... and for a long time most people used public transportation, or walked.
I graduated from high school and was in the USAF in 1958... I never had a drivers licence... certainly didn't care about fuel economy... or the absolute sweet spot of 48 mph (I'll bet there are some more dummies on the forum too, you may be one of the few that knows all of that stuff)
I always earned high wages... so I went quickly went from no car to a brand new truck and a brand new car a year apart... fuel at $0.27/gallon... high test. Drive all you want... never give it a thought... change the spark plugs every 3000 miles... tires lasted a little longer.
By that time... I had kids a coming and overtime to work... and my GI Bill for college. guess what... I was had majors in Chemistry, Zoology, and Botany... we didn't do anything with fuel economy... some were beggining to discuss enviromental issues.
Of course I'm not as smart as president Nixon... I never even thought about being president.
I knew that I was a dummie without being told.
Wow! 48 mph common knowledge!
Sleepy
