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Driver's license renewal

  1. Apr 23, 2010 #1


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    I have to get my driver's license renewed soon and I have to take the written test. Since it's been 10 years, I decided to look the test up on the DMV website. Good thing I did.

    Question: An extra 100 lbs in your vehicle can reduce gas mileage by what percent?

    WHAT?? What on earth does this have to do with knowing traffic laws?

    There is a second fuel consumption question that is more of a no brainer, but neither of these questions should be on a driver's license test.

    Who decides these things?
  2. jcsd
  3. Apr 23, 2010 #2


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    100lbs is barely an extra person in your car. I can honestly see if there was a concern of 500lbs. Perhaps the intent is to make someone fully aware of the impact of driving on the environment??
  4. Apr 23, 2010 #3
    I'd guess about 5%---

    maybe its about all those long distances in some of the plain's states with few and far between gas stations.
  5. Apr 23, 2010 #4


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    That is weird. I can understand questions that are not strictly about traffic laws if they deal with safe driving practices, but this seems to be off the wall.

    Even if it is meant to increase awareness of fuel conservation( something I could see on a driver's Ed class test, but not a driving test), It seems to send the wrong message. "Putting more weight in my car decreases my mileage, so car-pooling is a bad idea."

    Wait, you don't live in a state who's economy relies heavily on the Gas or auto industry do you?
  6. Apr 23, 2010 #5


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    No, I live in Kansas. What is the point of the extra weight? Is it a slam against fat people?
  7. Apr 23, 2010 #6
    That's interesting... I'm going for my Class 3A license (vehicles with more than 2 axles) and there are no questions that come even close to the impracticality of that.
  8. Apr 23, 2010 #7
    Isn't the answer "vehicle dependent" ?
  9. Apr 23, 2010 #8
    Forget the relevance of it, I'm wondering how you're even supposed to know that.
    I have a fat friend who has a fat wife and I've almost gotten into accidents underestimating how bad my braking and acceleration is with them in the car.
  10. Apr 23, 2010 #9
    What was the answer?

    It seems like it would affect mileage during acceleration and there would be slightly more rolling friction but wind resistance should still be the same, which on the highway would be the major cause of reduced gas mileage.

    Oh but they asked how much CAN it reduce gas mileage? Driving in the city and stopping every block for a traffic light would be about the worst case. I'm thinking 100 lbs/(weight of car) x 100%
  11. Apr 23, 2010 #10
    Maybe they should have asked how much it increases braking distance.
  12. Apr 23, 2010 #11


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    The answers listed are

    A) Up to 6 percent
    B) up to 5 percent
    C) Up to 10 percent
    D) Up to 2 percent

    I can't find anywhere in the driving guide that addresses fuel consumptiion, but the test they posted has two questions on fuel consumption. Only in Kansas I guess.
  13. Apr 23, 2010 #12
  14. Apr 23, 2010 #13


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  15. Apr 23, 2010 #14


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    Presumably the 2% is a federal standard.

    But isn't Kansas pretty flat? So in mountainous states with lots of gradients it would be more, while in high altitude states the fuel consumption would be lower, due to decreased aerodynamic drag, the effects of extra mass would be higher.

    I've just spent the day watching an entire season of "the Big Bang Theory" on DVD and I think it's affecting me .....
  16. Apr 23, 2010 #15


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    They ask important questions on the test where I live.

    If two cars going the opposite direction meet on a one-lane mountain dirt road overlooking a 400ft cliff, which car has the right of way? The car going downhill or the car going uphill?

    The right answer is that the car going downhill has to back up until they reach a point where two cars can pass side by side. Fortunately, they don't ask anything complicated like how wide the road has to be to pass side by side. Unfortunately, they don't specify whether the uphill/downhill refers to that particular instant or to the overall direction, nor do they get specific about what to do when the road goes over the top of a mountain instead of just dead-ending at the top.

    And the age old question where 4 cars arrive at a 4-way stop simultaneously, which car has the right of way? (The car to the right, of course. We're lucky we don't live in South Africa - they're required to use common sense and hand gestures to resolve situations like that.)
  17. Apr 23, 2010 #16
    that was worth a chuckle!
  18. Apr 23, 2010 #17


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    And the driver that politely waves the car to his right to proceed immediately assumes liability when that car is slammed into.
  19. Apr 23, 2010 #18
    The Mexican stand-off.
  20. Apr 23, 2010 #19
    I was in that situation once----all four cars started and went through at the same time, and there wasn't an accident
  21. Apr 23, 2010 #20


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    I'm going to quote dilledante on this one:

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