Something that I’ve noticed across most of the microwave ovens that I’ve used is that when they hum while cooking food, I can pick out 2 distinct tones. One of them is pretty clearly 60 120 hz, the 2nd harmonic of the AC power frequency. The other is consistently a minor 7th above that (which would be somewhere around 106-108 212-214 hz depending on the exact ratio). What causes this 2nd frequency to be produced?

Edit: after checking against a tone generator, the low frequency is actually 120 hz, double the grid frequency. The question is still the same, just an octave higher.

  • HerrBeter@lemmy.world
    link
    fedilink
    English
    arrow-up
    6
    arrow-down
    1
    ·
    edit-2
    1 year ago

    Mashed potatoes :

    Dice small, 10-15min

    Rice:

    1,5dl water to 1dl rice, 10-12min

    I could go on. It’s a big water heater

      • HerrBeter@lemmy.world
        link
        fedilink
        English
        arrow-up
        2
        arrow-down
        1
        ·
        1 year ago

        Only if you don’t turn down the power, you want full effect to get in to temp and then turn it down to keep temperature steady

          • HerrBeter@lemmy.world
            link
            fedilink
            English
            arrow-up
            1
            ·
            1 year ago

            I don’t think I specified, but much like cooking rice on a stove top you won’t run it at the same temperature. The microwave will use less energy than a traditional stove top, not sure about induction ones. And after learning to boil things with it, I do it all the time.

            Just get it to boiling then 450 then if needed 300

    • Clay_pidgin
      link
      fedilink
      English
      arrow-up
      1
      ·
      edit-2
      1 year ago

      I’ve never seen someone use Deciliters before! Love it. Disclaimer: I live in either the USA, Myanmar, or Liberia.