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Lost in progress
tom66:
--- Quote from: tggzzz on April 01, 2023, 03:36:54 pm ---Check the permissible errors in the values a speedometer displays :) Precision != accuracy :)
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The speedometer on my car is within 1 mph of GPS indicated speed.
tggzzz:
--- Quote from: RoGeorge on April 01, 2023, 04:58:41 pm ---Ok, so it seems both matters. It matters what one get used to (for the dial clock, which is not straightforward), then when it comes to straightforward like a speedometer, everybody agree the analog dial is easier to read.
About remember what time was it, for those who started with numeric display clocks, one more question please: when you have to remember "I've start soldering this PCB at 11:43, let's see how long it takes", do you remember 11:43 like a number, or like a snapshot picture of the display?
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Choose the best tool for the specific job. Best => you understand the job's requirements and the relative advantages and disadvantages of each tool.
tggzzz:
--- Quote from: tom66 on April 01, 2023, 05:22:01 pm ---
--- Quote from: tggzzz on April 01, 2023, 03:36:54 pm ---Check the permissible errors in the values a speedometer displays :) Precision != accuracy :)
--- End quote ---
The speedometer on my car is within 1 mph of GPS indicated speed.
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Measured with what tool with what specification?
tom66:
--- Quote from: tggzzz on April 01, 2023, 05:26:47 pm ---Measured with what tool with what specification?
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Measured by timing GPS positions over a period of time using an app, both my iPhone and my previous Android phone showing a GPS speed of 70 mph with the car indicating 70 mph over long periods of time in varying terrain, I have never seen the devices deviate more than 1 mph from the car's indication, with the car showing the higher speed.
There's no reason for a car to show inaccurate readings nowadays, the speedometer is calibrated against the tyres used at the factory and mine is running stock tyres. A wheel has a radius of about 20 inches (508mm) and might lose 8mm over its lifespan which would be 1.5% reduction in radius. So that would put it within 1 mph at 70 mph.
There are some people who seem to rely on the 10% under rule and drive at 77 mph believing they are actually travelling 70 mph. They are probably just lucky because most police forces only enforce at 10%+2mph, but this is only guidance and not law...
Siwastaja:
I disagree more than I normally disagree about nearly anything.
Analog clock is a total disaster, you can't see anything intuitively. The whole feeling of simplicity/intuition is because we have been taught how to read one since we were small kids. A LOT of effort went into that learning process. It's a complex parser.
Why? What is wrong with analog clock. Basically everything:
1) It does not correspond to the natural day-night cycle at all. It does not have 24 hours like the natural cycle. Two cycles are multiplexed into one actual cycle.
2) In most actual clocks that you can buy, the more significant, larger, better visible hand is minute hand. You don't get any rough idea about the time of the day by looking at the minute hand.
3) The minute hand points to some numbers directly. Great idea, you can accurately read the minutes there? Wrong! The numbers say: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11. You have to mentally multiple by five to get the minutes.
4) The small hours hand point to... nothing. The hours scale is missing. Not that it matters, the hours scale is accidentally at the wrong place (as explained above).
5) Want to have a rough idea of time, with a quick glance? No way, you see a graphical mess of two hands forming some kind of geometrical shape which means nothing.
I realize most people have probably forgotten how they had to learn the clock at school (or even before). If you don't remember it, you may think it works intuitively. It doesn't. Instead, we run complex parsers in our heads.
But in the end, time is a number. Just like how many apples John gives to Mary, or your math grade, or how long your penis is. Most of the people (especially >90IQ) handle numbers very intuitively. And this is exactly why the digital clock is so much better. There is no mental load, you directly load the number into your brain.
This is not to say analog is not intuitive. Quite the contrary! Analog panel meters are great; you get the approximate value with a quick glance (say, current 0-10A; are we close to overload or not?). We see good analog meters all the time, as in car speedometers, I have nothing to complain. It goes between minimum and maximum (with no strange 24-to-2x12 wrap-around), you will grasp the approximate speed in a nanosecond's glance, and then you can also read the speed accurately enough nearly as quickly as you do with a digital display.
But the analog clock is a colossally bad example of analog meter, because it's ****ed up beyond all repair. Make it 24 hours and remove the minute hand and I will reconsider.
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