hmm. the uni teacheris not so smart

[cryptokid]

my sister is going to the university of florida.
in one of her classes they are doing somthing or another with chemistry and the professor was explaining viscosity relating to vii's in motor oil, explaining how through modern science, motor oil is made to get thicker as it gets hotter, hence 5w30 etc.
he stated that it is through the use of vii's that makes motor oil thicker as it gets hotter. clearly this guy doesnt know what he is talking about. i had to school my sister on the workings of vii's and the whole motor oil weight classification system to correct him.
anyways, she told this to her professor and he called me ignorant!

i think a call to this guy is clearly in order, to school the teacher
you would figure some chemistry teacher in a fairly high rated school like the uni of florida would know a thing or 2 about vii's and their effect on motor oil, espically more than some dropout like me.

 

[labman]

No institution is free of over educated fools. I remember explaining to a guy with a masters in Chem E why he needed to put antifreeze in the radiator of his car.

 

[MolaKule]

quote:

---

he stated that it is through the use of vii's that makes motor oil thicker as it gets hotter. clearly this guy doesnt know what he is talking about.

---

Well, he is almost right. The VII additive increases in viscosity as the oil get thinner with higher temperature, so that the oil doesn't get too thin, and allows the oil to maintain a multigrade nature at the low and high ends of the temperature scale.

Draw a line from upper-left to lower right. This is the line for the oil. Now draw a line from upper-right to lower-left. This is the line for the VII. The vertical scale is the viscosity, the horizontal scale is the temperature. Where the two lines cross shows the oils average viscosity.

Now we know that this isn't the only way to do it. Mixing various viscosities of synthetic oils will also get you VI spread.

 

[Rick in PA]

I once had an engineering instructor state that the pressure inside a balloon was equal to the atmospheric pressure. I intuitively knew it was higher, so I challenged his assertion. He challenged me back to prove it. I went home, whipped-up a little experiment and proved the pressure inside the balloon was higher than atmospheric pressure. At the next class, we reviewed it, came to the conclusion that the higher pressure inside the balloon was due to the elastic nature of the balloon and the instructor declared himself "corrected". Thank-you Prof. Buzzard, you tought me to THINK.

Your sister should offer to run an experiment measuring the viscosity of various motor oils (straight weight, multi-weight, synthetic) at various temperatures and then chart the results. If he's a good teacher, he will welcome the challenge. If he's not a good teacher...

[ February 14, 2004, 12:53 AM: Message edited by: Rick in PA ]

 

[Mystic]

The public school system in this country is a disaster. There is no correcting it. The only answer is charter schools.

 

[giant_robo]

mystic,

yes.

no, we have to.

no, why do you think it's the only answer?

 

[Al]

What he said is right. I assume he meant that the oil really doesn't get "thicker"-it just assumes a "thicker" grade when hot

 

[wulimaster]

It could just be the teachers lack of effective communication skills.

 

[Gary Allan]

quote:

---

What he said is right. I assume he meant that the oil really doesn't get "thicker"-it just assumes a "thicker" grade when hot

---

So what you think "is missing" is that he asserts ..but doesn't express.. that the oil is thicker then it would have been at that temperature without yablabla?

 

[msparks]

I would be so easy to prove him wrong.

Just take the viscosity at 40C in cSt. then take the viscosity at 100C.

5w30 at 40 is 45.0 cSt.
5w30 at 100C is 8.9 cSt.

Should have said throught the use of VII's that an oil will not get as "thin" at temperature with a multi-vis oil as a straight weight oil.

Hope this helps.

 

[Rick in PA]

I googled for a graph, but couldn't find what I wanted. Well, at least I did find an elementry school student that did some work in this area for the California State Science Fair: http://www.usc.edu/CSSF/History/2003/Projects/J1531.pdf

Not a bad job either, just wish they had included a graph.

 

[labman]

Hey that Ramine did a nice piece of work. I hope the judges appreciated it. gives us some hope for the future.

 

[Mystic]

giant_robo, I think you agree with me that the public school system is a disaster. I don't think there is any correcting the problems because the teacher unions will not allow correction of problems and there is too much attention paid to politicial correctness in the schools. It is often very hard to fire a poor quality teacher, thanks to the teacher unions. But on the other side of the coin there are school administrators who are hopeless cases. I personally had experience with a former school district administrator and let me tell you he was a hopeless case. He engaged in favoritism, I know he fired some good teachers, and he engaged in political correctness to the nth degree.

Charter schools are the answer. They have to be more responsive to the desires of the community, and higher standards of education are EXPECTED at the chapter schools.

Most of the problems in the schools are the fault of teachers and school administrators.