Today I Learned

[jim hardy]

Today I learned that a Blob, is the inch version of a Slug, does anyone remember how excited they were when they learned that ?

No, just now learned it , Thanks !

But i was excited by the Poundal, force to accelerate a pound of mass one ft per second² , so is around a half ounce.

 

[fresh_42]

A good friend, a WW2 veteran, ...

I do this whenever I get a chance.

So I may ask you for this favor, and tell him a big, honest and seriously meant thank you from my side.
He and his comrades let me grew up in a world of respect and tolerance instead of violence and fear. I haven't forgotten this fact.
Usually I'm not a big fan of American military interventions in parts of the world they don't even understand. To be honest: I hate it.
But here in Europe it worked, and worked out well. I do not even dare to think about the alternative. That's the main reason I defend the EU as successful concept, too. I know to value these facts. And I haven't forgotten the reasons.

 

[RonL]

No, just now learned it , Thanks !

But i was excited by the Poundal, force to accelerate a pound of mass one ft per second² , so is around a half ounce.

That might help a little, I'm trying to learn how to calculate turning a big heavy flywheel from 0 to about 30 turns in about 5 seconds normally I would just throw some junk together and do a little test, but this is much bigger than my junk box but my brain has been awakened a little

 

[jim hardy]

That might help a little, I'm trying to learn how to calculate turning a big heavy flywheel from 0 to about 30 turns in about 5 seconds

start by calculating its moment of inertia I, then torque = I X dω/dt and energy = ½ I X ω²
http://hyperphysics.phy-astr.gsu.edu/hbase/mi.html

i did that once long ago. My flywheel was easy, a uniform disk of 39⅜ inch diameter (1 meter how convenient) by 4" thick so to calculate I was trivial.

old jim

 

[Ibix]

A good friend, a WW2 veteran, described his kidney stone as "Worse by far than when i got shot " .

I saw my dad floored, pretty much literally, by a kidney stone. Such a tiny thing when it finally emerged. His dad had one in the 1930s. I've no idea if a propensity is hereditary, but I make sure to drink lots of fluids regularly...

 

[OmCheeto]

start by calculating its moment of inertia I, then torque = I X dω/dt and energy = ½ I X ω²
http://hyperphysics.phy-astr.gsu.edu/hbase/mi.html

i did that once long ago. My flywheel was easy, a uniform disk of 39⅜ inch diameter (1 meter how convenient) by 4" thick so to calculate I was trivial.

old jim

That's the easy part. (I've already done all that)
The hard part is analyzing the method with which RonL wishes to apply the torque.
Fortunately, 256bits gave me a grand idea on how to simplify the problem, by pointing out that this is similar to a bifilar pendulum.
Grand experiments to follow...

ps. I'd never heard of a "bifilar pendulum" before, so I'll count that as my "TIL" item.
pps. I've also learned about a bazillion other new things over the last 7 days, but didn't mention them, for the sake of bandwidth.
One example: The animal that is killing all the fish at Yellowstone National park doesn't have a "HOX" gene. [ref]

 

[fresh_42]

I've no idea if a propensity is hereditary, but I make sure to drink lots of fluids regularly...

I occasionally add citric acid to the water I drink for this reason. I've read somewhere that it might help. Since it doesn't hurt as long as it isn't exaggerated, so what. Perhaps I should try and find out whether it's a urban legend or there is some truth to it.

 

[Sophia]

I occasionally add citric acid to the water I drink for this reason. I've read somewhere that it might help. Since it doesn't hurt as long as it isn't exaggerated, so what. Perhaps I should try and find out whether it's a urban legend or there is some truth to it.

My friend had a kidney stone (it was removed by ultrasound as Jim said) and doctor advised her to drink non alcoholic beer.

 

[fresh_42]

My friend had a kidney stone (it was removed by ultrasound as Jim said) and doctor advised her to drink non alcoholic beer.

What a horrible advise in a country where Plzeňský and Budějovický are basically local brands!
(I find my solution better.)

 

[beamie564]

A good friend, a WW2 veteran, described his kidney stone as "Worse by far than when i got shot " .

My dad had stones in his kidney. One night it got really bad; it's the only time I've ever seen him cry.

 

[Pepper Mint]

My dad had stones in his kidney. One night it got really bad; it's the only time I've ever seen him cry.

I had a family member having them too. The cold and fever like symptoms the patient exhibits look terrifying. I once almost had one on my right as diagnosed by my doctor and she advised me to take a lot of fresh water and daily physical exercises. I almost couldn't take it when trying to bend my body down if I didn't do what she told me within two days; you know the muscle fatigue arose around my waist and my whole body skin became more sensitive than usual when the pain came.The problem went away after a few months following her advice. Now I'm having a habit of taking a pretty large amount of water every day.

 

[beamie564]

she advised me to take a lot of fresh water and daily physical exercises

That helps. My dad was also told to drink barley water and ( as Sophia mentioned) non alcoholic beer.

 

[Fewmet]

No, just now learned it , Thanks !

But i was excited by the Poundal, force to accelerate a pound of mass one ft per second² , so is around a half ounce.

Today I learned these posts are about physics, not invertebrate biology.

 

[Tsu]

I was able to enjoy (!) my first kidney stone last October. My stone was 5mm and I took drugs for over a week to try to pass it but ended up with hydronephrosis and almost became septic. My doc finally scheduled me for surgical laser lithotripsy after I puked in his office and he blasted my stone and put in a stent that tap-danced all over the top of my urethra for two weeks. Miserable! I was off work for a month!

 

[OmCheeto]

TIL that it is not illegal to drive a car barefoot.
It was apparently an urban myth.

Driving Barefoot: The Eighth Deadly Sin? [Car Talk]
Tim Cotton
SEP 2, 2016

 

[Stephanus]

Today I learned about RODC (Read Only Domain Controller).
I've had a confusion for a week.

"What if you log on a RODC and add a user there?"
So it was a WRONG question.
The right question would be
"What if you log on a RODC and run ADUC (Active Directory User and Computers) to add a user?"
The answer would be:
ADUC will add the user to the DC (Domain Controller) with which it connects to.
And ADUC will never be able to connect to RODC. Even though it runs on RODC.

 

[Pepper Mint]

If you are unsure about what you learn, you can make questions about it directly on board.
TIL that a man having a female portrait or face shape can grow some beard to increase his masculine look. He'll look a lot better than most of other bearded men who usually look a lot more masculine after shaving. I want to do that but I seem to have always had such a low testosterone level since my birth that no hair grows on my face at all.

 

[Drakkith]

Today, in my C programming class, I learned:

while ((studentInClass == true) && (studentAwake > 0)
studentAwake = (studentAwake - 1);

if ((studentInClass == true) && (studentAwake <= 0))
return(ZZZzzz...);

 

[mfb]

If your program works properly, you can replace it by
if(studentInClass == true && studentAwake>0) {
studentAwake==0;
return(ZZZzzz...);
}

Assuming studentAwake is an integer.

 

[jim hardy]

what do the double operators in mean, == && ?
Does C use integer 0 and -1 for true & false , like Basic ?

 

[Ibix]

C has the fun feature that you can do assignment anywhere. So if(x=1) assigns 1 to the variable x, and 1 counts as true. So x is set to 1 and this if block always executes; the else block never will. The double equals is a comparison - so what I probably intended was if(x==1). To avoid the gaping pitfall here you will often see C programmers write if(1==x) because if they accidentally forget the second equals they'll get an error trying to assign a value to 1.

The double && is an and statement. A single & is a bitwise-and. It treats its arguments as binary and returns the result constructed from doing an and on each bit in turn - so 2&3 is interpreted as 010&011 and returns 010, which is 2.

 

[mfb]

"a=5" means "set a to 5", so the comparison needs a second "=".
"a && b" is just the regular logic "a and b". "a & b" is bitwise and.

0 is false, everything else is true.

 

[jim hardy]

Thanks guys.

As you see, i never learned to "C"

old jim

 

[Pepper Mint]

...
Does C use integer 0 and -1 for true & false , like Basic ?

C'ers also use true and false as 2 boolean values.
bool doX(bool x)
{
If (x) return false;
else return true;
}

 

[Drakkith]

Assuming studentAwake is an integer.

Opinions differ. Some say studentAwake is an integer, but may not have been properly initialized in the morning. Others say the student was never declared awake in the first place.

 

[Stephanus]

Today, in my C programming class, I learned:

while ((studentInClass == true) && (studentAwake > 0)
studentAwake = (studentAwake - 1);

if ((studentInClass == true) && (studentAwake <= 0))
return(ZZZzzz...);

Shouldn't it

char *Laugh(char *s) { return("ZZZZzzzz"); }
for(;studentInClass && (studentAwake>0);studentAwake--);
if(studentInClass && (studentAwake<=0)) return(Laugh("LOL"));

 

[Astronuc]

TIL that "The Texas health department doesn't track deaths . . . from antibiotic-resistant infections, and neither does the CDC." Apparently, many states don't require notification, and death may be attributed to other causes - "only 17 states require notification of C. difficile infections, for example, while just 26 states and Washington, D.C., do the same for MRSA."

Patients need to know this information.

'Superbug' scourge spreads as US fails to track rising human toll
http://www.foxnews.com/health/2016/...s-as-us-fails-to-track-rising-human-toll.html

 

[Stephanus]

what do the double operators in mean, == && ?
Does C use integer 0 and -1 for true & false , like Basic ?

I'm afraid if I answer this I'll get warning . But everybody did,
Okay here we come.
"==" is comparison, as everybody else says.
But "=" is an assignment and AN OPERATOR.
Okay, here's the example.
Let's say we involved 2 variables. B and C
A = B == C, a will be 1 (in C, -1 in BASIC) if B equal C, 0 (either C or BASIC) if otherwise.

In C
A = B = C, A will be C (and B will C as well). It's an assignment and operation.
In BASIC
A = B = C, A will be -1 if B equal C, 0 if not. It's a comparison not assignment.
Pascal
A:=B:=C, is an error expression.

Well actually the above example
A = B == C is error in BASIC there's no == operation.

What's interesting in C is = is an operator. Consider this format
A = B + C;
A = B - C;
A = B = C;
A = B / C;
All are valid.

What is && as compared to &?
&& is a logical operator.
& is a bitwise operator.
Because this is not programming language forum, I can't go further on the risk of getting kicked .

And I will conclude this post by BOLT
Binary One, Logical Two!
& is binary AND
| is binary OR

&& is logical AND
|| is logical OR

 

[Stephanus]

...0 is false, everything else is true.

Yes and ... no.
b = 5;
if (b) printf("Morning\n"); else printf("Night\n");
b = 8;
if (b) printf("Morning\n"); else printf("Night\n");
Both will print "Morning"
But, b = 4 > 3, b will be 1 (-1 in basic). Not everything else .

It's been a while with BASIC.
Do anybody remember?
B = 5
if B then print "MORNING" else print "NIGHT", will B have to be 5 not -1?
This I forget.

 

[mfb]

If you assign "true" to an int or a float it will be stored as 1, it cannot get multiple values of course. But ever non-zero value will be interpreted as true if it gets converted to bool (e. g. in an if statement).