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John Cuthber

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Posts posted by John Cuthber

  1. You need a whole bunch of solutions (all dissolved in water)

    25% Ferrous oxalate 

    Concentrated ammonia (not specified, but probably 25% w/v or thereabouts.

    A saturated solution of oxalic acid.

    Unfortunately, ferrous oxalate isn't very soluble in water. So the first of those is impossible.

    So this is going nowhere.



  2. 48 minutes ago, Complexity said:

    c is only constant in a vacuum !


    C is "the speed of light in a vacuum".

    And so  C is constant.



    12 minutes ago, Complexity said:

    I deem you haven't give me an answer yet to my question . 

    But, in the real world, we can see that the answers are right here in this thread.

    You are just ignoring reality.

    How do we distinguish that from trolling?

    51 minutes ago, John Cuthber said:

    Please stop putting forward stuff that can be destroyed with just a few moments' thought.

  3. 1 minute ago, Complexity said:

    Isn't the force noticed by the speed of c ? 


    Since c is a constant it can't change under the influence of a force so it wouldn't tell you if that force was there- that' idea is just silly.


    2 minutes ago, Complexity said:

    How could anyone notice something if they aren't looking for it ?

    By that stupid argument, nobody notices anything new.


    Probably the best known example is the precession of Mercury.

    They noticed it many years before they knew what explanation to look for.

    Please stop putting forward stuff that can be destroyed with just a few moments' thought.


  4. 3 hours ago, Complexity said:

    You would be the ''adverb'' . 


    "You" is a noun. Misusing Words like "adverb" doesn't help.

    3 hours ago, Complexity said:

    It is a causality answer and not meaningless .  

    Plainly wrong because, as it happens, I didn't use force and a knife.

    I used a super-power laser.

    But I got the same answer.

    That's what people here are trying to explain to you.

    The answer is the same - regardless of the mechanism.

    The density of an apple is a little less than 1 gram per cm3

    I can make use of that fact by comparing it to the density of water, and, since the density of water is 1, I can predict that the apple will float.


    But, because I'm clever enough not to insist on asking "how is the apple divided?", I can make the same prediction without actually dividing the apple at all.

    So, when I go apple bobbing, I'm not stuck with a bowl of apple soup.

    3 hours ago, Complexity said:

    My suggestion that lower energy is somehow an attractive force is not ''way out there '' over the top in imagination , based without fundamental  foundations . 

    Yes it is.

    Simply because any such force would, by now, have been noticed.

  5. If you want to be stupid about it, you can consider density  in terms of physically splitting things.

    If I take an apple and dice it into 1cm cubes then the number of cubes I get is (approximately) the volume of the apple.

    And, I have similarly shared out all the mass of the apple among all those cubes.

    The density of the apple is the average mass of each cube.


    The question "what divides the apple?" is a bit meaningless, but as good an answer as any is "my imagination".




  6. 20 hours ago, MigL said:

    Using that logic...
    Since missiles don't have 100% kill ratio, it wasn't just the missile that brought the plane down.

    The logic is that you can't say it's 50% without further data.
    It doesn't say much else.



    If a hunter mistakenly shoots a man because he thinks he's a bear, is it the bear's fault, the victim's fault or the man who didn't make sure before he pulled the trigger's fault?


    On 1/15/2020 at 12:32 AM, MigL said:


    If the Iranian missile radar interrogates only on mode 2, and receives no reply; what is the operator to do ?
    Further, he tries to contact his superior, but unreliable Iranian comm. systems make it impossible; what is the operator to do ?
    He only has 5 -8 seconds to make up his mind; what is he to do ?

    Let's be clear about this; before you do something that may kill a lot of innocent civilians, you should put a lot of care into verifying ID.

    If you don't have the data on which to make that decision, you don't shoot.

    Shooting "blind" is not acceptable.

  7. 6 minutes ago, ScienceNostalgia101 said:

    Wasn't sure whether this belonged in physics or chemistry, but being that from my familiarity with physics, heat makes objects LESS conductive, I

    Only with metals.

    With electrolytes and semiconductors, they generally conduct better when hot.


    However, you may be right in thinking that chemistry gets involved, heating cellulose- a poor conductor- converts it to charcoal- a much better conductor.


    Also, flames are quite good conductors compared to air

  8. On 1/11/2020 at 8:27 PM, MigL said:

    Root cause analysis

    In this case, do you consider the root cause to be Trump, his Iranian counterpart, whoever "pulled the trigger" or what?


    It's not clear what the aviation industry can do about this.

    It's not as if the Iranians had announced that they were going to attack an air base and (more or less) consequently,  power up their anti- aircraft  weaponry. 


    If you are not careful, you get into the realms of "victim blaming".

    You can take your pick about whose" fault" this massacre was, but it's not the airline.



  9. 20 minutes ago, michel123456 said:


    That is the post that bothers me.


    Re. " there is the side that is ignorant and/or lying. "

    In fairness, I think you might want to consider "misguided" as a possible third option, though some would say it's a subset of "ignorant".

    Psychotic is also a possibility.
    These 4 options can be summarised as Wrong, Wrong, Wrong and Wrong.

  10. 48 minutes ago, Cynic said:

    I doubt the ability to accurately measure global temperatures as precisely as have been claimed, with the exception of the only very recent measurements obtained by remote sensing. Much of the data is collected from stations never intended for the purpose of determining global climate change.

    Why would the purpose of the data  recording matter?

    50 minutes ago, Cynic said:

    I feel like the odd man out on this man made global warming thing.

    I invite you to contemplate why that might be.


    50 minutes ago, Cynic said:

    Climate has changed repeatedly and dramatically over the millennia with the complete absence of man made technology, or even man for that matter. It seems perfectly reasonable to believe that current changes are due to factors similar to what have happened throughout earth’s history, not something that came along in the last blink of an eye.

    The recent changes in climate, like the "rise of man" have both happened in the blink of an eye.


    We know that CO2 levels have gone up .

    We know the temperature has gone up.

    We know that CO2 is a greenhouse gas.

    In effect, what you believe is that we put  another blanket on the bed, and we are now warmer, but the two things aren't related.

    Are you surprised that you are called "called stupid, brainwashed, denier, ignorant of science, "?

    And, of course there's this aspect of it.


    climate cartoon.JPG

  11. 5 hours ago, gatewood said:

    To simplify, the less I have to do or put into the process, the better.

    Buy washing soda on-line.

    5 hours ago, gatewood said:

    I can get that energy from, wood, charcoal, methane, etc.

    All of which cost money.

    Even if the only money they cost is the money you don't get by selling them- the so called "lost opportunity cost".

    14 hours ago, gatewood said:

    II. Yes, I've already done that by: ...


    14 hours ago, gatewood said:

    you think it could work?

    Well, which is it?

    Have you done it  (in which case you know it works) or not?

    Anyway, if you leave a solution of sodium hydroxide exposed to teh air, it reacts with CO2 and then dries out to give a crystalline carbonate (probably the monohydrate, though that depends on local conditions)

  12. If there was a cheaper way to do it, the commercial manufacturers would use that way.

    As it stands, sodium carbonate is already very cheap.


    You could, just to be different, separate chloride from sodium electrolytically- producing HCl and NaOH.

    And then you could react the NaOH with CO2 to give Na2CO3

  13. 6 hours ago, Sensei said:

    The simplest brute-force dividing algorithm in C/C++ would look like:

    int quotient = 0;
    while( dividend >= divisor ) {
       dividend -= divisor;
    int reminder = dividend; // subtraction failed

    "subtract divisor from dividend until dividend is greater than or equal to divisor".

    The number of repetitions on the loop will be O(quotient)


    The more sophisticated version could left-shift divisor prior subtraction from dividend. Each binary left-shift operation is multiplication by 2. At the same time value added to quotient should be multiplied by 2. (In binary numeral system left-shift is equivalent of multiplication by 2, move the all bits one position to the left and make room for 0 at the end for the least significant bit)

    So e.g. division of 1000 by 50 will look like:

    temporary_quotient = 1;

    1000 > 50 (true)

    50*2 = 100, temporary_quotient*2 =2

    1000 > 100 (true)

    100*2=200, temporary_quotient*2=4

    1000>200 (true)

    200*2=400, temporary_quotient*2 =8

    1000>400 (true)

    400*2=800, temporary_quotient*2=16

    1000>800 (true)

    800*2=1600, temporary_quotient*2=32

    1000>1600 (false! We are using previous values and subtract it from 1000! i.e. 800 and 16)

    1000-800=200, quotient += temporary_quotient (16)


    Repetition of entire procedure once again:

    temporary_quotient = 1;

    200 > 50 (true)

    50*2 = 100, temporary_quotient*2=2

    200 > 100 (true)

    100*2=200, temporary_quotient*2=4

    200 == 200 (they are equal, end of the loop)

    200-200=0, quotient += temporary_quotient (16+4=20)


    50 * 20 = 1000


    That reminds me that the single division operation in machine code of Motorola 68000 (Amiga 500, Atari ST) was talking over 150-170 cycles of cpu (running at 7.16 MHz) (unsigned integer div faster, signed integer div slower). So at max it could do just 7,160,000 / 150 = ~47,000 divisions per second.


    I know it's just an illustration of the point but, it's worth mentioning that you should check that you are not trying to divide by zero, or you get stuck in an infinite loop.

  14. On 1/4/2020 at 5:01 PM, Rachel Maddiee said:

    If the group ends in the suffix -ite(with less less oxygen atoms bonded), it changes to -ious

    No, it changes to "-ous".

    Sulphurous, nitrous etc don't have an "i".

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