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Cake day: June 11th, 2023

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  • I’ve stopped a half dozen people from doing something like this… Every single one of them was filling up to the maximum pressure listed on the sidewall.

    The sidewall pressure is only the correct pressure at the maximum load on the tire. The maximum rated load on the tire is often nearly twice the vehicle’s maximum weight rating, so the sidewall pressure is never the correct pressure for your vehicle.

    The correct pressure for each tire on your vehicle is listed on a tag on the driver’s door, or door frame.











  • No, you’re not understanding me correctly. Mostly because I misspoke, so that’s on me, not you.

    The contact patches I was talking about are the corners of the rectangle. Everything between the wheels is the footprint.

    The area of the footprint basically determines the minimum MPG you can have. (The more complicated point is that it is related to all the vehicles you produce rather than a specific minimum, but that overcomplicates the issue. The point is that CAFE standards provide strong incentives for manufacturers to increase the “footprints” of their vehicles. The larger the footprint they can claim, the less MPG improvement they need to make. So, longer and wider wheelbases.


  • It is “necessary” for them to be that wide.

    CAFE standards are based on “footprint” which is basically the rectangle of the tire contact patches. If you’re a car manufacturer who can’t meet the NHTSA’s MPG requirements for the size of car you produce, you can increase the size of your cars, so they fit in a larger class that requires less of an MPG improvement.

    The most effective way to increase the footprint is to widen a narrow car, increasing its footprint toward square.


  • Rivalarrival@lemmy.todaytoComic Strips@lemmy.worldWide Cars
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    7 days ago

    Yeah, nobody wants wide cars. Manufacturers are making them wider to make it easier for them to meet NHTSA’s CAFE standards.

    The standards require year-on-year MPG improvements. The problem is that they require proportionally more improvement on the smallest, highest economy cars, and less improvement on the largest, lowest economy vehicles.

    The standards are based on the “footprint” of the vehicle: the rectangle between the contact patches of the tires. The larger the area of that footprint, the larger the vehicle, and the less MPG increase it needs to have.

    So, they are pushing the wheels toward the corners, and widening the wheelbase, approaching a square to maximize their footprints. They are making cars bigger and boxier so they don’t have to make them more efficient.

    Fuel economy of the cars on the road is actually falling, because manufacturers are effectively prohibited from continuing to make their smallest, most efficient vehicles. They are compelled to either discontinue those vehicles, or embiggen them to fall in a larger class.


  • You’re cooking dinner, not crystal meth.

    “Frozen chicken strips” doesn’t mean what you think it means. “Frozen chicken strips” are “whatever neutral solid you want to use to carry the flavor of everything else in this dish to your mouth”.

    “1 cup” of them is “However much of that solid you feel like eating with this meal”, plus any remaining that would be less than a full portion if saved for the next meal.

    Forget the scale; if you’re dirtying a dish for a cup of chicken, you don’t belong in the kitchen! The proper tool for measuring a cup of frozen chicken is your dominant hand, curled into a fist around them.


  • Fahrenheit is also based on water’s phase changes,

    Exactly: It puts 180 degrees between boiling and frozen, as though they were opposite conditions or something.

    It’s set at 32 instead of 0 because 0 is the temperature of the most stable frigorific mixture they knew of. If you don’t have access to a reliable thermometer for your lab, the thermometer you make and calibrate with Fahrenheit’s brine method is going to be more accurate than the one you make for Celsius’s freezing/boiling method.




  • In duodecimal, 10 is, indeed, the sum of 6+6. Add up 6+6 in your number system. The number you reach equals “10” in the number system I described.

    Hexadecimal is a wonderful base, as it is the composite of 2 * 2 * 2 * 2.

    But, it does not allow for even division by three or six, and that is a problem. The simplest regular polygon is an equilateral triangle. The angle of an equalateral triangle is 1/6th the angle of a complete circle. Hexadecimal cannot represent 1/6th of a circle without a fractional part. Geometry in hexadecimal would require something like the sexagesimal layer (360 degree circle) we stack on top of decimal to make it even remotely functional.

    Duodecimal would not require that additional layer: The angle of a complete circle is “10”. The equilateral triangle angle is “2”. A right angle is “3”. A straight line is “6”.

    With duodecimal, the unit circle is already metricated. Angles are metric. Time is metric.

    Let me put it a different way: Our base is the product of 2 and a prime number. A 12-fingered alien who came across our decimal number system would think it about as useful and practical as we think of base-14, another number system with a base the product of 2 and a prime number.