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Electric or mechanical scale to weigh yourself?

  1. Electric

    2 vote(s)
    25.0%
  2. Manual

    6 vote(s)
    75.0%
  1. Aug 30, 2008 #1

    tgt

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    Which one would you pick for your scale and why? Have a vote (mechanical=manual in poll) .

    The question boils down to which is more accurate?
     
  2. jcsd
  3. Aug 30, 2008 #2

    lisab

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    If you're trying to lose (or gain?) weight, accuracy isn't as important as precision.
     
  4. Aug 30, 2008 #3

    Moonbear

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    True.

    I've owned both, and they both gave similar readings. Mechanical scales usually have markings for every pound, and you can see if you're somewhere between pounds. Digital scales give readings in half pound increments. Since weight loss and gain is only meaningful when it's more than a pound or so (anything less can be daily fluctuations in water retention or other things that have nothing to do with muscle or body fat that people are interesting in gaining or losing), either one is adequate.
     
  5. Aug 30, 2008 #4
    Neither one. Body composition is independent of weight. Also, clothing sizes are not listed in lbs. Ditch the scale and get a measuring tape. It is cheaper and gives better information than a scale.
     
  6. Aug 30, 2008 #5
    I have a mechanical one that really sucks. If you stand closer to the middle, your weight is lower. It's impossible to get precise readings out of the thing.
     
  7. Aug 30, 2008 #6

    turbo

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    Spring scales may or may not be accurate and their performance will change over time due to wear.

    Balances (platform scales with sliding weights on beams) are quite accurate and do not drift as much, but they are expensive.

    Electronic scales using strain-gauge technology are not much more expensive than spring scales and are far more accurate. They also cost a lot less than balance scales and take up considerably less room, with about the same accuracy as balance scales.
     
  8. Aug 30, 2008 #7

    Gokul43201

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    Mechanical balances.
     
  9. Aug 31, 2008 #8

    tgt

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    Don't understand.
     
  10. Aug 31, 2008 #9

    tgt

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    why?
     
  11. Aug 31, 2008 #10
    What she's saying is that it's more important that you can tell how much weight you've lost than how much you weigh, e.g. you weigh 190 but the scale says 140. Okay, so that's bad. But if it can accurately display a 20lb drop, i.e. you go to 170 and the scale says 120, then you're still good to go.
     
  12. Aug 31, 2008 #11

    tgt

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    yeah okay. But what happens if I'm trying to measure myself against standard weights? Then accuracy is important.
     
  13. Aug 31, 2008 #12

    vanesch

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    I prefer the electric scale: its batteries are always empty :redface:
     
  14. Aug 31, 2008 #13
    Manual. I don't understand the mechanics behind the electric scale, and until I do, I can't trust it.
     
  15. Sep 1, 2008 #14

    vanesch

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    That's a strange way of thinking. Do you also use a mechanical computer ?
     
  16. Sep 1, 2008 #15
  17. Sep 1, 2008 #16

    vanesch

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    :rofl:
     
  18. Sep 1, 2008 #17

    Gokul43201

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    Wow. That's a dead on identical (except for looking newer and shinier) abacus to one I have at home.

    tgt, mechanical balances need little in terms of recalibration. Cheap op-amp circuits have thermal drifts in gain that can be as large as 1 part in a few hundred per K. And the electronics will age, in addition, creating long term drift. Strain gauges will also experience fatigue (though only on the order of 10^5 or more cycles).
     
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