Sensei

News to me; I learned it in chemistry.

It matters when you learned it the first time, not the last time.

I had it the first time, on physics, in primary school, or early high school

Ideal gas law was proposed by Clapeyron

https://en.wikipedia.org/wiki/Benoît_Paul_Émile_Clapeyron

"Benoît Paul Émile Clapeyron 26 February 1799 – 28 January 1864) was a French engineer and physicist, one of the founders of thermodynamics."

(wikipedia doesn't mention he was chemist, according to current terminology)

Everybody who is doing thermodynamics starts from ideal gas law.

https://en.wikipedia.org/wiki/Thermodynamics

"Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work."

Obviously chemistry lesson must have it, so the same as lessons about protons and electrons bound together to form Hydrogen, then to H₂ gas, and how to make it, in reaction releasing this gas.

So the same electronics lessons mentioning about electrons. It's quite inevitable.

Classic physics deal with physical object changing state (like solid<->liquid<->gas<->plasma), and how they behave over time, in some system, and never deal with change of contents of compounds.

Nobody will be learning on physics what happens if you use HCl + NaOH->NaCl+H₂O. It belongs to chemistry lessons.

In the case of quantum physics, decay of unstable isotope to other element, change this. But it's special case.

It was a slip of the tongue. Of course I meant "gas law is physics".

Is it true that Cavendish did indeed discover most of the gas laws before the the people they are named after?

And also why was he such an introvert?

 

first topic in the chemistry section.

Gas law is physics, not chemistry.

and second question is rather.. psychology?

Neither one fits chemistry section though..

GPS in mobile phone is not very accurate. Its reading jumps few meters to dozen of meters. My Samsung Galaxy S5 has options to enable/disable GPS from satellite and/or "GPS" from cell towers. There is huge difference in quality of signal from satellites and cell towers. Which can be easily seen turning one or the other on/off and walking city with Google Maps for instance. In village with a few distant cell towers around situation can be different and GPS from satellites could show more accurate result.

I have written Android app reading GPS from device, putting data to database, writing CSV file row, and adding it to listview on the screen.

Then wait second, or specified amount of time, and repeat.

It's consuming battery as hell.

Walking with Google Maps turned on, and we can literally see how percentage of available power is decreasing, IIRC 1-2% per minute of usage, so whole battery lasted for 70-80 minutes of experiment.

GPS devices are more expensive than RFID tags.

But everybody have mobile phone with GPS these days. It's just a matter of writing software for existing device at hand.

BTW,

It's illegal to distribute and sell Android app which is monitoring activity of user without his/her knowledge and permission in the Google Play Store.

So unfortunately won't be able to release soft for f.e. monitoring wife/husband activity. At least not without making whole website and store.

Hey every body.. peace be upon you.

well i have to make a science project for our university science fair. i am thinking of making Discharge tube.

can anyone guide me? how to prepare it... have you experience of it?

or any other idea?/

Which gas do you want to showcase in discharge tube?

Each gas has slightly different color, spectrum lines of element, revealing transitions.

Hydrogen? Oxygen?

Then you need to know how to produce them, like here, while electrolysis of water:

(don't use typical Gold ring, as it's 14 or 18 carat Gold, with 58.333% and 75% Gold abundance, the secondary metal will react and destroy your ring)

Maybe Carbon Dioxide gas?

From reaction between Sodium Bicarbonate and almost any acid (Acetic Acid is cheap and widely available).

Once you have round-bottom flask filled by gas of your choice, you need power supply of high voltage.

It could be Van de Graaff generator, Cockcroft-Walton generator. Depends on what you have at hand.

And put wires to up-side-down placed flask, in such way they wont be connected, wet, and don't introduce Oxygen to flask (especially important with Hydrogen).

Decreasing pressure of gas in tube/flask, would help to reduce needed voltage to start discharge.

Once you have ready discharge tube, you can pass light from it through prism, and show spectral lines on some white screen, calibrated and with scale 400nm to 700nm.

(cops who want the collar, prosecutors looking for wins), you probably aren't going to see anyone who really cares about justice until the trial.

That's unfortunately true. They generally stop searching, when they find the most suspected person, which the last visited or saw victim, which might not be the right person (like with example of the last visitor in apartment leaving fingerprints/DNA on wine/coffee cup).

That's why such person, suspected by them, is the most interested to be no more suspected.

No, it's not one example. It's hundred cases here for the last 10-20 years or so. It's routinely done for the all missing people who were not found.

Any media known case (longer missing than a week, or two, with suspicious disappearance), press inform "family,friends,boyfriend were tested on lie detector and passed through it"..

This allows police to concentrate on searching people, instead of observing (ex-)boyfriend, family members, etc.

I gave the only example that I remember when family member disagree to pass through it.

Here, it's almost routine, to check parents on lie detector, when child is missing (or other family member is missing).

The only one time when parent, actually mother, didn't want to pass through it, was the case when mother actually killed her baby daughter..

After she refused to go through lie detector, pressure made by her own family, 24h/d, mother by law, her husband, were so overwhelming, that she break apart, and revealed that she killed her.. And where body is buried..

They later revealed that they were going after her, the whole day long, telling her "we know you're f**ing lying, tell the truth" etc.

All because of her refuse to being examined (the all other family members were tested without any objections).

A graduated cylinder measurement will not result in a reading of "there is no liquid in the cylinder". The error is quantifiable. A lie detector on the other hand, is measuring a boolean state: true or false. There is only one error mode: maximum error (unless you waffle and say "inconclusive". Can you get such a result with a volume measurement?). You have false positives or false negatives. So the assessment moves to the rate of false positives and false negatives, and the impact they have.

It's not just boolean true or false in the case of lie detector. There is list of dozen questions.

List of dozen truth questions person has to answer. List of dozen lie questions person has to answer.

From it, examiner is learning, how body of somebody is behaving when he/she is telling truth (just saying something from memory), and when he/she is making stuff up.

Then graph is checked against to compare, with questions that are important.

If graphs from test "truth questions" won't match each other, and important question,

or test "lie questions" won't match each other, and important question,

the whole examination is void. As person is trying to cheat examiner.

The same is done with voice recognition and comparison of signature: there is data to examine, and there is reference, to compare against it.

(see MRI lie detector checking brain activity during making stuff up, versus remembering it from memory)

Obviously it's useless for somebody with mental problems, or who has hallucinations.

But such person would be excluded (or at least should be) from being interrogated by court also!

I gave example of graduated cylinder not accidentally.

I knew somebody will tell that volume will be volume, no matter what, like Greg H.

It's analogy and example of unexperienced lie detector examiner.

Who does not know that pressure and temperature have to be taken into account while reading data..

Please notice, in the case of this thread, there are two lie detections which should be done: one with Anita Hill and C.Thomas.

Problem would be if lie detectors would show up that they both saying truth. As their versions are mutually exclusive.

DNA and fingerprint evidence are supposed to exclude >>99% of the population (when done correctly).

That depends where DNA is found. On victim or somewhere in room.

If police or prosecutor found DNA on coffee or wine cup, in a room of deceased murdered person they will treat person whose DNA is on it, as the first one to be suspect.

So better don't go to somebody apartment just in case he/she is murdered an hour later, as you will never be able to clean from accusations...

There is plentiful examples, were somebody visited deceased person, or even lived with him/her (how they couldn't leave DNA everywhere?), and police used DNA found on place to prosecute innocent, even though there were people swearing they were with him/her later when murdering happened and they could not do it..

Lie detectors have nowhere near the same level of confidence.

Nobody seems to understand that in 99% it's not important what lie detector will show up.

What matter is reaction of somebody to fact they will be examined.

The real guilty will fear it and decline passing through.

While innocent will have no objections to being examined and instantly agree to do it to have peace.

Within a frame energy is conserved. Between frames it is not.

 

m²c⁴ = E² - p²c² is invariant, while the individual terms on the right-hand side (E and p) are not.

Take for example decay of unstable isotope in a box.

At the beginning of experiment atom has rest-mass m₀

thus energy E₀=m₀c²

(it's in the same frame of reference as box)

After decay one decay product has rest-mass m₁,

but relativistic mass is [math]m_1\gamma_1[/math] and energy is [math]E_1=m_1c^2\gamma_1[/math]

Second one has rest-mass m₂,

but relativistic mass is [math]m_2\gamma_2[/math] and energy is [math]E_2=m_2c^2\gamma_2[/math]

Total energy E₀, prior decay, is equal to E₁ and E₂ (plus what they gave away to medium) at any time after decay:

E₀=E₁+E₂

Initial mass is sum of relativistic masses of decay products:

[math]m_0=m_1\gamma_1+m_2\gamma_2[/math]

Decay energy is:

[math]D.E.=E_0-m_1c^2-m_2c^2[/math]

[math]\gamma_1[/math] and [math]\gamma_2[/math] are not constant. They are decreasing from their maximum at decay moment to 1.0 with time. While particle decelerate passing through medium in a box.

If you will start analyzing it from frame of reference of particle that decayed, box will be accelerated in direction of particle movement instead, and particle stationary.

So, just to be clear, both mass and energy are properties of a system and inexorably linked.

Yet one is frame dependent and the other is not.

 

Is this because of what we choose to define as 'mass' ?

When swansont says "mass" he means "rest-mass". Somebody else might interpret it as "relativistic-mass".

That's why I am always saying rest-mass or relativistic-mass to not confuse reader, which one I had in mind.

I think what he meant was:

When computers started out the entire user interface was a terminal, similar to the command-line prompt in Windows or the terminal in Linux.

You're right. I rushed too early to reply. Have to remember to reread fiveworlds posts multiple times prior replying.

When computers were just starting out the entire computer was basically a command line like command prompt on windows or the terminal on linux.

Linux the first version was released 1991..

https://pl.wikipedia.org/wiki/Linux

It was not "command-line prompt on Windows", but MS-DOS for IBM in 1981.

https://en.wikipedia.org/wiki/MS-DOS

A graduated cylinder doesn't change volume depending on the liquid being measured, the time of day, and whether or not it's having a bad day.

Yes, it does. And liquid too. It's called thermal expansion.

https://en.wikipedia.org/wiki/Thermal_expansion

Being too small, does not mean it's not existing.

Some alcohol meters (Thermohydrometer) has thermometer inside, to be sure at which temperature reading of volume is done.

http://www.ebay.com/itm/Proof-and-Tralle-Hydrometer-Alcoholmeter-Distilled-Spirits-Moonshine-Alcohol-USA-/291510995251

See, there is even table attached what readings will be at which temperature.

In the most of court cases there is no need to ask details during lie detection test. The all details were (or at least should be) given during testimony.

Just ask questions:

"did you lie during testimony?"

"did you hide some important information during testimony?"

etc.

Just to correct some misinformation, that appeared earlier in this thread, about usage in court:

According to various sources:

"in Japan, polygraph evidence is admissible in court".

Also

"In one US state, New Mexico, polygraph evidence is (conditionally) admitted in the same way as other scientific evidence."

http://lawschool.unm.edu/nmlr/volumes/13/3/07_note_lie.pdf

"In the United States, most states permit polygraph test results to be used as evidence where parties have agreed to their admissibility before the examination is given, under the terms of a stipulation. "

http://www.polygraphis.com/WebsiteFAQ.htm

In the laboratory you use f.e. graduated cylinder 100 mL, that has +-1 mL (+-1%) tolerance.

And you don't complain that it has not perfect accuracy.

And yet you complain that lie detector has no absolute accuracy.

Everything has some tolerance for error in measurement. It should be calculated at the end of measurement.

UI means User Interface.

The all modern operating systems have their own UI (or GUI = Graphical User Interface).

Search terms in Google.

Chikis, when I am having objections what result will be I am opening Open Office, entering some random chosen a,n (f.e.), and math formula.

f.e. in your case:

A1=some a

B1=some n

C1=A1-B1

D1=A1+B1

E1=C1/D1

F1=-E1 (or -1*E1)

Then you can make a graph:

A2=A1+1

select some A fields,

Edit > Fill > Down.

And whole A column is filled with values incremented by 1 (for example).

Then fill the rest B-F

Select E column, and make line graph from it. You see how it's changing with variable a.

I wondered if anyone could give this figure 1612.903 a bit more clarification within these two examples for me?

Looks like numerology to me...

That should be the number of metres in a mile. But it is wrong, it should be 1609.34

But there is no single definition of "mile".

There is Roman mile, English mile, Scots mile, Welsh mile, Russian mile... etc

https://en.wikipedia.org/wiki/Mile

Even now there are three: International, nautical and U.S. survey mile..

The fact is, this is very old news - there wasn't enough evidence to keep Thomas off the bench then, there hasn't been enough to have him impeached since his confirmation, and I sincerely doubt there will be any more truthiness to be found in a made for HBO movie about the subject.

What evidence are you talking about, when in such cases there are always only word versus word?

She passed lie detector test, he refused.

What else evidence can be added or found.. ?

None.

There is word of politician/judge/celebrity/etc high society member versus somebody else much lower class, typically.

In her case, she was also from almost the same class, attorney, professor on University, and yet her word was ignored, and she discredited.

If professor in University testimony, supported with lie detector test, is not reliable, then whose testimony is reliable, especially "John Doe".. ?

It's not about molestation, but about lying in front of commission which is supposed to investigate whether nomination is good choice or not.

What is sense of existence of such nomination commission if they are biased, and ignore everybody testimonies.. ?

All of you are simply supporting view that people should not come up with true, just keep mouth shut and mind their own business.

Because if people will tell truth, against high society member, they will be discredited and their life devastated.

That was in 1991. You fail to answer my question about why all of this is suddenly earth shattering news now, 25 years later.

Because now (16 April 2016) was released movie about this story.

http://www.imdb.com/title/tt4608402/

I'm confused. Dude has been a sitting Supreme Court Justice for like...20 years? What's all the hubbub, bub?

https://en.wikipedia.org/wiki/Clarence_Thomas_Supreme_Court_nomination

http://www.imdb.com/title/tt4608402/

The allegations didn't come out until after the nomination.

Such allegations always appear after the fact.

There would be no nomination (or whatever else) in the first place, if allegations would be known in the past. Isn't it obvious and logic.. ?

Your point is void.

It looks like this:

There is president, prime minister, minister, parliament member, or other politician, celebrity, etc.

Somebody with knowledge how to speak, who is used to public speeches, eloquent, intelligent, with team of lawyers and people who advice behind his/her back what to tell, and how to tell to people believe.

And there is average "John Doe",

Alone, without anybody who will advice (and if there are some, they are from opposite to politician group, which means they degrade his appearance (because of their own politician reasons)).

Person who is not used to public speeches, who is afraid of them, and being attacked by either media and people supporting politician. His/her life will be examined with the all detail to discredit him/her and immediately brought to press to make unbearable pressure on him/her.

There is his word, against "John Doe" word. In front of cameras.

Person will end up talking cheap. And nobody will believe.

Obviously everybody will rather believe politician, as he/she can persuade people to believe. After all without this ability he/she would not be promoted.

Now, "John Doe" pass through lie detector without any objections, while politician refuse to be examined.

In her case, Anita Hill, it was secretary of parliament member, who was member of parliament commission investigating nominations,

who called the all old employers asking "do you know of something about C.Thomson what could discredit him?"..

There are a lot of reasons that I don't think Clarence Thomas is a good Justice,

For example??

If you don't know him in person, there is no single reason, you would vote for him not for being judge..

but lie detector tests are extremely unreliable and I have trouble faulting anyone who doesn't want to take one.

What a gibberish.. Only people with serious crime on conscience can say so...

(who can try to discriminate finger prints?

who can try to discriminate DNA test?)

Lie detector is extremely good and reliable.

It's no joke, one guy in front of me, told he is murderer,

he used to be soldier, commando member..

Lie detector is just a single step from reading mind.

If you put lie detector of somebody lying, he/she will sweat instantly...

Testimony in front of God (typical one for now), versus testimony with lie detector, the most reliable one, is second one,

If somebody tells me that lie detector is unreliable it's immediately turning red light, that they committed some serious crime they won't people know about it...

Delta1212, what did you do.... ?

Trying to discredit lie detector is like trying to discredit finger prints, or trying to discredit DNA tests, but lie detection tests are more reliable. As people know what they did or didn't. While finger prints one can leave accidentally (drinking tea/coffee for example).

Clarence Thomas, disgusting nomination, and betray of democracy..

Guy who molested womans, she passed lie detector test (Anita Hill), he has been nominated to US Supreme Court Justice...

That's disgusting to justice. Until he pass through lie detector test. Which he will never do...

That's disgusting to democracy.

ps. if you would put him in front of lie detector, he would piss off, because of afraid of being examined....

ps2. I don't want to be accused to attacking just russians. Like here:

http://www.scienceforums.net/topic/94549-russian-democracy/

Nationality does not matter, really. It matters what you do, and who you are, really.

I will threat all sides equally.

How do I show, prove, see or be convinced that

If we have equation in form:

[math]\frac{a}{b}=\frac{c}{d}[/math]

We can multiply both sides by b and receive:

[math]a=\frac{b*c}{d}[/math]

Then multiply both sides by d and receive:

[math]a*d=b*c[/math]

In your case it's:

[math]-\frac{bp}{cp-a}=\frac{bp}{a-cp}[/math]

so after rearranging it's:

[math]-(bp*(a-cp))=bp*(cp-a)[/math]

[math]-(bp*a-bp*cp)=bp*cp-bp*a[/math]

[math]-bp*a+bp*cp=bp*cp-bp*a[/math]

[math]bp*cp-bp*a=bp*cp-bp*a[/math]

I need something to learn and know and do within a duration of 6months. Something that'll make me certified in its aspects and also make me saleable amongst my counterparts.

6 months?

It's way too small amount of time to learn anything to be ready.. Unless you will be doing it at home 14h/d, writing projects for yourself the whole day.

Do you already know C,C++,C# .NET Framework,Java,JavaScript,PHP,anything?

The financial and material resources to learn such a computer program wouldn't be a problem.

Buy C,C++ book (or use C/C++ on-line learning materials),

download and install free Visual Studio Express from MSDN http://msdn.microsoft.com/vstudio/express

and start writing. At the beginning book will have some examples (typically taking arguments from console and output to console, such tools are now obsolete, now matter GUI).

Something that you would use by yourself.

For instance make math calculator as project.

Make GUI in GUI builder, learn how to attach code to execute after user clicked and interacted with common controls (button,text,listview,progress bar etc.),

One such project a day, in 6 months you will have 180 apps, and plentiful of experience, with code that you can actually show.

Electronics engineer should be familiar with robotics, so get arduino uno starter kit.

f.e.

http://www.ebay.com/itm/New-Ultimate-UNO-R3-Starter-Kit-for-Arduino-1602-LCD-Servo-Motor-Relay-RTC-LED-/221451495178

You will have to join electronic circuit knowledge with a bit of programing.

After weeks you will have enough knowledge for f.e. making led advertising boards with programmable and animated content.

And sell or lend them to f.e. shop owners directly.

I'm from a country where the chances of employment is close to minimum.

Computer programmer can work anywhere,

as you just need good English (already you have),

computer or laptop, permanent Internet connection,

and PayPal account to receive money from your clients.

Google for "freelance programmer"

What is your country?