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Gravitational Distribution

  1. Aug 19, 2012 #1
    Hi all,

    Problem ; Why a car consumes different amounts of fuel on two different roads with same characteristics only with different locations ?


    -Amounts of fuel consumed, lengths and slopes of two roads are measured precisely.
    -Two roads are built from the identical material thus friction force is same in both.
    -Car has the same load including driver in both two measurements.
    -Identical fuels are used in both two measurements.
    -Car was driven with identical characteristics in two measurements.

    Surely there might be other parameters that needs to be considered for performing such a comparison but these are the ones that comes to my mind mainly.

    My potential explainations ;

    1- Gravitational distribution on Earth or object due to space is not homogeneous ?

    2- Different altitudes have different pressure values that can directly/indirectly effect the operation of the internal combustion engine
  2. jcsd
  3. Aug 19, 2012 #2
    Wind. Temperature (of air, tyres, road). Humidity.
  4. Aug 19, 2012 #3
    Temperature is the same as well.

    Wind and humidity ; up to what percentage can these parameters be effective ?

    Let's say 10lt/100km for no wind and humidity is at reference cell.

    What would the average wind and average humidity correspond to in liters/kilometers ?
  5. Aug 19, 2012 #4
    For wind, much depends on the shape of the car and the direction and the strength of wind. It is not entirely implausible to speculate that it is possible for a car arrive at its destination by wind alone.

    I am less sure about the temperature and humidity, this will require a careful analysis.
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