• 0 Posts
  • 33 Comments
Joined 2 years ago
Cake day: July 3rd, 2023
  • jeinzitoAsk Electronics•USB PD for older deviceEnglish
    8·
    1 month ago

    I’m not sure about the standard - but in my experience, if a PD trigger IC requests 12V, that will be supplied, no matter the current draw. I have used this to power several low power devices, for example a 12V computer fan, and I have also verified this with no load at all. There is also PD PPS, which could be used to deliver 14V or any other voltage.

    Edit: I normally use this kind of trigger board, they are available everywhere online.

  • jeinzitoich_iel@feddit.org•ich🚄🔊👿iel
    4·
    4 months ago

    Das ist mir tatsächlich vor Kurzem so passiert - drei Betrunkene mit fetter Musikbox, direkt neben mich und voll aufgedreht, dann auch noch das Bier umgeschüttet und beim Losfahren das rollende Bier- und Musikboxtransportgerät im Gang an die Trägheit verloren.

  • jeinzitoAsklemmy@lemmy.ml•How much flow and volume from urination do you need to levitate your whole body for two seconds off the floor?
    40·
    8 months ago

    Aerospace engineer here. To levitate, the force of the exhausted mass flow (F=ṁ×v) has to equal the pull of gravity (F=m×g) on your body. The gravity of earth is g=9.81N/kg. Wikipedia says the average body mass is 62kg. It also says the bladder capacity of an adult is about 400ml, and I’ll assume the density to be 1kg/l. You want to levitate for 2 seconds, so your mass flow needs to be ṁ=0.4kg/2s=0.2kg/s. If you rearrange the equation, you get v=m×g/ṁ=62kg×9.81N/kg/(0.2kg/s)=3041m/s.

    So if you manage to pee with a velocity of about 3km/s, you can levitate for 2 seconds with an average sized bladder.

    To achive that, your “exhaust” must be clenched to a diameter of about 0.29mm. This gives a cross-section of 0.066mm² or 6.6×10^-8m². Multiply that with the velocity of 3041m/s and you again get your flow of 0.2l/s.

    Of course, during those 2 seconds you loose mass and therefore, earth’s pull on you gets less and you start to accelerate to about 0.23km/h, reaching a height of 4cm. If you took your special bladder to space, we can use the rocket equation to calculate that this stunt would accelerate you to 3041m/s×ln(62kg/61.6kg)=19.7m/s=71km/h

  • jeinzitoAsklemmy@lemmy.ml•Any good games you can Reccomend?
    1·
    9 months ago

    The Long Dark? Offline single player survival in the postapocalyptic Canadian wildernis. There is a survival mode in which you can freely explore, but also a story mode and several challenges. In my opinion an extremely beautiful game and on the higher difficulties also extremly challenging.

  • jeinzitoPrivacy@lemmy.ml•*Permanently Deleted*
    6·
    10 months ago

    I can’t say anything in regard to modern printers, but I don’t trust any proprietary device connected to the internet. I have an old inkjet and an old laser printer, both without network functionality themselves - but I connected them via USB to a Raspberry Pi, which runs a printer server and makes them available on the local network. I can print and scan from my Linux laptop, and I also managed to print something from my Android phone. Haven’t tried Windows yet. Configuration of the Raspberry Pi was easy, especially enabling scanning via the network.

  • jeinzitoOpen Source@lemmy.ml•SF ads call out tech firms for not paying for open source
    5·
    1 year ago

    Do you have an example? I am pretty sure that a FOSS license which requires companies to pay is impossible.

    Open Source guarantees that anyone can give the software to a company for free:

    “The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license shall not require a royalty or other fee for such sale.”

    And it guarantees that the company can then use it freely:

    “The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business […]”

    Quotes from the Open Source Definition.