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  • Question about bitcoin forking and Proof of Work?

    So, to my understanding, a new block is supposed to be added to the blockchain every 10 minutes (ish)

    Though when this happens, more than 1 block can be added, and we have a 'fork' where there are briefly multiple chains. As soon as one fork becomes longer than the other, this fork becomes the main fork, and all the blocks on the other fork are disregarded.

    My question is, what happens to all the valid transactions in the disregarded forks? If I'm sending bitcoin to a merchant, and this transaction is only included in a fork that is later disregarded, then from my view the transaction is rejected for no reason. It seems possible, although incredibly unlikely, that you could be unlucky enough for your transaction to end up in a disregarded fork forever. Is this a real problem or have I misunderstood something about the nature of which transactions go into which blocks?

  • Microphone problems in Windows 10?

    I have a headset with a microphone on it, when I plug it into my computer it recognises it and if I right-click on the megaphone icon in the Icon Tray and select 'Sounds', then go to 'Recording', my microphone shows up and the sound bar next to it changes as I speak. The sound bar fills up completely, suggesting to me that Windows is picking up all of the sound, though maybe I don't know how this sound bar works. In the microphone's properties, the 'levels' are at 100% and sample rate is at maximum (16 bit, 48000 Hz, DVD Quality).

    However, I have tried Discord, Messenger and even just Windows' built-in voice recorder app, and in all cases, I have to almost have the microphone in my mouth and be shouting for people to be able to even slightly hear me, and even then it's seriously quiet. The fact that Windows seems to be picking up all of the sound, but every app is picking up barely any of it, is very confusing to me. Does anybody know what's going on here?

    1 AnswerOther - Hardware4 months ago
  • What does the Chinese script in the background of the intro to Avatar: The Last Airbender translate to? ?

    During the 'Water, Earth, Fire, Air' part, the characters have Chinese symbols behind them... Does anybody know what the letters translate to?


    Languages7 months ago
  • Anyone know how to use Trenchbroom?

    Using Trenchbroom, I don't own a copy of Quake, I'm just using it to make .map files for another program. I have a bunch of .wad texture files, but I can't load any of them in. If I drag and drop it, nothing happens. The '+' button in the 'Texture collections' section is greyed out. In their tutorial, it says to go to 'Edit > Map properties', but I don't have an option called Map Properties under Edit.

    Any ideas how to load textures into Trenchbroom? Do I need to change a setting somewhere to be able to import them? Thanks

  • View Google Drive files in Android file explorer?

    I have an MP3 player on my phone, and on my PC I have about 75GBs of MP3 files. I would love to transfer these MP3 files to my phone, but my phone doesn t have enough storage space for this, so I have stored it in Google Drive.

    The MP3 player on my phone allows you to select any folder from either the phone s internal storage or an SD card, and it will open all the songs it finds in that folder.

    Is there any way to create a link to my Google Drive folder somewhere in my Android s file system, so that I can open them in the MP3 player? The player does not, as far as I can see, have support for any Cloud services.

    Accessing Google Drive folders from file explorer is easy to do in Windows, I m just curious if the same can be done on Android.

    2 AnswersGoogle9 months ago
  • Electronics question - output frequencies of modualted dual-555 astable?

    So for an A-level project I'm working on, I need to decide on and calculate the output frequencies similar to the 'Dee-Dah' circuit shown right at the bottom of this tutorial:

    I asked these questions on the site over a month ago, but I haven't had any replies yet so I thought I'd ask here as well...

    Firstly, what difference does the 10k resistor between pin 3 of IC1 and pin 5 of IC2 make compared to, say, a 1k resistor?

    Next, unless I’ve calculated something wrong, the output of the second astable on its own would be 585Hz (1.44 / (24.6k * 100n), and the actual output is 300Hz and 660Hz. How do you calculate the output frequencies? Like, if I wanted the ‘dee-dah’ to be 400Hz and 800Hz, for example, what would I have to change?

    What difference does the 100 microfarad capacitor? make at the output of IC2?

    Why does the total resistance of the loudspeaker and resistor have to be 100 ohms?


    1 AnswerEngineering3 years ago
  • tkinter transparency?

    Windows in tkinter can be made transparent with root.attributes("-alpha", Alpha). Is there a way to make frames transparent? I keep getting ('Frame' object has no attribute 'attributes') as an error message.

    1 AnswerProgramming & Design3 years ago
  • Python - need help understanding OOP (with tkinter)?

    I've been struggling for at least 4 years to understand anything about OOP, and now I actually need to use it in my coursework, my lack of ability to understand it is really becoming a hindrance. I'm trying to set up a very basic GUI using classes. This is the code I currently have:

    import tkinter as tk

    class window:

    def __init__(self):

    self = tk()

    self.title('A-Level ')

    self.attributes("-fullscreen", True)

    win1 = window()


    However, as you may have guessed, this does not work.

    I always thought OOP worked a little bit like a function. 'win1' would be passed as 'self', so when 'self = tk()', 'self.title()' and 'self.attributes()' were called, they would be applied to win1 and passed back. Clearly, my knowledge on the matter is hugely lacking, so any information on how this is actually supposed to work would be greatly appreciated.

    4 AnswersProgramming & Design3 years ago
  • Superheterodyne receiver question?

    I fear I may have missed some vital information here...

    So in the mixing/heterodyning stage of this reciever, fo - fc is the intermediate frequency. According to this handy little book I have, this frequency always contains the audio signal from the original radio station, no matter what station is tuned in.

    Except, it also says this intermediate frequency is always exactly the same (around 450kHz). So any radio signal that come in, comes out as 450kHz.

    But they also all come out as the original radio signal.

    That seems somewhat contradictory to me, what have I missed? Thanks.

    6 AnswersPhysics3 years ago
  • Python to exe file?

    I've been trying to convert this Python program into an exe file that can run on computers that don't have Python. I've tried pyinstaller, but I always get the error message 'failed to create process', and I tried cx_freeze, which compiled and created an exe file successfully, but the exe created comes up with an error message 'Python error in main script'. However I can run the .py script in IDLE without any errors or problems, so I'm not sure what the problem is.

    I'm using Python 3.5.2, and I think tkinter might be causing the bulk of the error messages I'm getting. Any advice on converting .py to .exe would be appreciated!

    1 AnswerProgramming & Design3 years ago
  • Can you find an unknown function, f(x), from saying f(0) = 4 and f(2) = 4?

    In other words (but with a different function), g(0) = 8 and g(2) = 6, find g(x). I'm only writing this extra bit because Yahoo answers won't let me submit this question. It keeps saying 'Tell us some more'. So I'm just literally typing whatever comes to mind. Nope, still can't submit that, ok. You're getting a running commentary of my thoughts right now, which is pretty cool IMO. Don't let it distract you though. This question is very important to me and I would like to know the answer. Wow, I still can't submit this. It's over 500 characters at this point and I still can't submit it. Insane. I mean, how long does it have to be, Yahoo? People don't want to read a book every time they answer a question. This probably got boring for most people a few hundred characters ago. Some people, ey?

    6 AnswersMathematics3 years ago
  • Is it true that a blind man who had surgery to be able to see committed suicide?

    Apparently he was born blind, and he couldn t cope with the weird new experience. One of my friends told me about it, but I can t find the article, but that might be because I m not good at typing the right keywords into Google. Just want to fact check it before I claim it to be true to anyone else. Thanks!

    2 AnswersPeople with Disabilities3 years ago
  • Where can I find a wireless (Not Bluetooth) speaker?

    I m looking at buying a speaker for my desktop, but I don t really have to space to be dealing with wires, so I was looking into a wireless speaker. I soon realised the latency of Bluetooth speakers was too high and easily noticible when watching videos or playing games, but I can t find really any wireless speakers that aren t Bluetooth, especially that are also under £100. Any help on where I could find a speaker like this would be greatly appreciated

    2 AnswersMusic & Music Players3 years ago
  • How do you prove this maths equation?

    If you have (√2)/2, how do you prove that it's equal to 1/√2?

    6 AnswersMathematics3 years ago
  • Sum of x² from sum of x?

    If you don't know the values of your X variables, but you do know what Σ(x) is, can you work out Σ(x²), or vice versa?

    1 AnswerMathematics4 years ago
  • If electrons flow slowly in a circuit, how are they manipulated so fast in computers?

    So apparently, electrons flow at a speed of only mm/s in a circuit, as oppoed to the speed of light I ve always been told for simplification up until now. I m just a little confused therefore on how electrons are manipulated so quickly in a computer.

    The processor is ~5x5cm as far as I can remember, so how does it keep swapping electrons in and out of it s registers? Moving 5cm from one end of the cpu to the other would take an electron travelling at 1 mm/s 50 seconds, which clearly is far longer than it actually takes. Even more than that, the cpu sends and receives data from up and down the entire motherboard, to/from secondary storage etc. Surely if electrons move so slowly then it would take minutes to go from the cpu, through the motherboard, through the SATA cable and into the hard drive?


    3 AnswersPhysics4 years ago
  • A-level exam proof question "A line and a quadratic curve never meet"?

    The straight line with equation y = 3x - 7 does not cross or touch the curve with equation y = 2px² - 6px + 4p, where p is a constant.

    Show that 4p² - 20p + 9 < 0, and hence find the set of possible values of p.

    So I think I have an idea of how to do this in a general form, but not specifically. I think you need to find the minimum point of the curve when the line and the curve just touch, and then do something from there. I might be completely wrong though, hence why I'm asking here. That, and I can't figure out how to find the minimum point of a curve with an equation like that...

    2 AnswersMathematics4 years ago
  • Why does current flow from positive to negative?

    Isn't current just the flow of electrons? And aren't electrons negatively charged? If those are both the case, does that not mean that electrons would be attracted to anything positive, and therefore current would flow from negative to positive? Really quite confused by it all, I've obviously missed something pretty important somewhere along the line...


    6 AnswersPhysics4 years ago
  • Hide quick access ribbon in Microsoft Word?

    How do I get rid of the 'Quick Access' ribbon in Microsoft word? The only options it seems to give me are 'show above the ribbon' and 'show below the ribbon', but I don't want it there at all.


    1 AnswerSoftware4 years ago