Huh what? I’m calling bogus on that. How do you enter feet and eighths of an inch, pounds and ounces, into a calculator? What keys do you use to change these “settings”?
OK, why don’t we convert time to the metric system? Why are we sticking with 60 seconds to the minute, 60 minutes to the hour, etc? If it’s fine and dandy to change every other form of measurement why is time sacred? Why can’t we change how we measure time?
Littlemouse…You can call it bogus if you want…just google TI 89 manual before you put your foot any further in your mouth…:=) When I retired, we were using TI-89 calculators in my classes. They had function buttons that allowed you to enter fractions either as mixed or improper. You could then put a measure key for conversion to another unit measure. I don’t have the same ipad symbols to show it exactly, hope you get the point. It was a real pain to compute everything in feet and inches. Metrics for linear measure, capacities etc. ruled for us. That does not mean that final answers were not in feet and inches if it matched the unit measure in our problem. We would immediately convert to metrics, do all of our computations, then leave the answer to a problem in form expected from that use in the problem.
StuckInPA…
The metric system is traditionally used for weight, volume and capacity and not time. So 50 kph (kilometers per hour is proper) Because, As far as time is concerned, in science,we use the unit that is most convenient. Days,hours, minutes, seconds and years are not arbitrary like feet and inches.They have relevance to our planet in space and just as proper to use as any time measure. But, we often converted everything to decimal units for computation (3.567 years for example) then convert back to days, hours etc. as needed when finished. But,the modern computer makes much of his irrelevant will digest and spit back anything. Hence, my previous comment that the computer has actually delayed our conversion…but it WILL happen, someday.
Ok, not bogus. My computer locked up every time I tried to download the manual.
“StuckInPA February 19 Report
OK, why don’t we convert time to the metric system? Why are we sticking with 60 seconds to the minute, 60 minutes to the hour, etc? If it’s fine and dandy to change every other form of measurement why is time sacred? Why can’t we change how we measure time?”
Because there is no reason to? Since we already have a system that’s universal for all practical purposes. That’s all the metric system is. There’s no reason they couldn’t have based it on 60 too.
The second is the SI unit of time. Days, hours, minutes, and years, not so much.
“my computer had trouble downloading it…” proof positive the TI89 was/is ahead of it’s time, even for some computers like yours that still use dot matrix printers, tube monitors and RAM the size of a desk top calculator. :=) Actually, we in education had access from Texas Instruments to down load the TI89 program, so our lap tops could function somewhat like them. Not perfect. Heck, you can’t give away the store.
“OK, why don’t we convert time to the metric system? Why are we sticking with 60 seconds to the minute, 60 minutes to the hour, etc?”
Because time is really based on real life, just like metric temperature measurement. 0º = freeze 100º = boil. Time is based on the rotation speed of the earth with 24 hours equal to one trip around the earth at the equator.
Besides the TI-89…In the past 10+ years there have been some calculators designed for the carpenter.
And now you can get the modern version…An app for your I-Phone
“Time is based on the rotation speed of the earth with 24 hours equal to one trip around the earth at the equator.”
Huh what? What do you mean “at the equator”?
The earth’s speed at the equator is fastest because it has the greatest distance to travel around it’s axis. Many equatorial references are used for that reason and others. It wouldn’t make much sense to use the poles where the rotational speed is minimal and any other place has a speed between them.
As many of you already know, the equator is a great circle, that is a circle with the center at the center of the earth. The distance between any two points on earth is it’s shortest along a great circle drawn between them. A case where the shortest distance between two points is a curve, not a line. Assuming you do no tunneling of course. The equator, being a great circle where you are traveling through space the fastest, at least in one dimension, makes it a prime reference arc for lots of stuff.
Having never read a book, I was unfamiliar with the concept of the Great Circle.
So how is time based on speed when speed is distance over time?
See what I did there? You made a great circular argument.
It doesn’t matter what latitude you’re on, you’ll go around once every 24 hours. If you’re standing right at the earth’s axis you’ll spin once every 24 hours.
Littlemouse…l.l.You asked "what do you mean at the Equator?"
Just an explanation of why the equator is often used as a reference circle, no more, no less.
Just to answer your other question …time equals distance (circumference) over rate (speed). So, both the distance and rate can be less, anywhere else on earth other then the equator and the time, 24 hrs, remains constant. 48/2=24…96/4=24…for non related examples.
An example of a not so great explanation…but at least not circular.
Your curse is never to have read a book, mine is never to have read a book that was of interest to anyone else.
Metric/english/SAE … so pedestrian.
Poor mortals. The supreme system for measurements under a yard/meter is picas and points as used in the printing industry. It’s base 12, as in 6 picas/72 points to an inch. Divisible by 2,3,4,6 and 12. Makes carpentry an absolute breeze. Easy to hairline close without having to squint and fuss over 1/8, 1/32nd and 1/16ths and segmenting with ancient old fractions.
As we converted over to computers for advertising composition at The Miami Herald newspaper in the late 1980s, I used to perform funky base 12 math in my head all evening and the time flew by. Need to center art within a 25 pica, 7 point, standard two columns Run Of Paper sizing?? Just deduct the (example) 9 picas, 9 points width of the art from 25p7 = (15p 10) divided in half, or 7 picas, 11 points.
It helped to be somewhat autistic and really, really wound up on diet coke. When the third generation Macintosh computers loaded with Adobe software came along, they did all the calculations in any format for us and included (sob) a stinking, filthy “center” function.
“Just an explanation of why the equator is often used as a reference circle, no more, no less.”
My qualm about that tied into my issue of using speed to define time, since speed = distance over time.
“Just to answer your other question …time equals distance (circumference) over rate (speed).”
So, you are saying that time = distance over (distance over time). Never having read a book, I had to figure that out on my own.
You are still using time to define time, which gets back to my point that you can’t use the earth’s rotational speed at the equator (or anywhere else) to define time. You are a Great Circler.
Not that Wikipedia is infallible, but “Time is one of the seven fundamental physical quantities in the International System of Units. Time is used to define other quantities — such as velocity — so defining time in terms of such quantities would result in circularity of definition.”*
*Duff, Okun, Veneziano, ibid. p. 3. “There is no well established terminology for the fundamental constants of Nature. … The absence of accurately defined terms or the uses (i.e. actually misuses) of ill-defined terms lead to confusion and proliferation of wrong statements.”
Such as defining time in terms of speed and therefore in terms of time.
bespoke: while I heart picas and points, that’s not what “base twelve” means.
Littlemouse…you do need to read books, occasionally. Taking statements out of context just to be argumentative is a sure sign of “too much time on your hands”. Go read a book…a science book. Take your time. We’ll wait.
You might see that we define terms as used in science, as a mathematical or algebraic relationship stated in other terms which is often algebraically changed for problem solving. Of course, you know that, and you’ll take this out of of text too. Algebraically substituting a quantity from the original definition you want into a relationship just to cancel out terms in the original relationship then stating it as circular reasoning is a waste of time…get a life ! I’m not impressed that you passed first year Algebra without reading a book.
And I was being so gentle. “get a life !” is quite the ad hominem but I believe I can take it. The context is further up this very page. I’m not going to reproduce your entire post each time I point out an error. Here’s the hard truth:
“Time is based on the rotation speed of the earth with 24 hours equal to one trip around the earth at the equator” is simply NOT TRUE.
And it’s not true because it’s circular.
“You might see that we define terms as used in science, as a mathematical or algebraic relationship stated in other terms which is often algebraically changed for problem solving.”
That doesn’t affect the fact that you say “Just to answer your other question …time equals distance (circumference) over rate (speed).”
And therefore you are saying that time = distance over (distance over time).
Which, not to belabor the point, is a CIRCULAR argument.
To sum up, “Time is based on the rotation speed of the earth with 24 hours equal to one trip around the earth at the equator” is, was, and always will be wrong.
Let’s look at the algebrabble, shall we?
“Just to answer your other question …time equals distance (circumference) over rate (speed).”
t=d/v the assertion
t=d/d/t v=d/t, just spelling it out
t*d/t=d multiply each side by d/t
d=d and the two t’s cancel out, proving that…
1=1 by dividing each side by d.
Congratulations! You are correct in that 1 does indeed equal 1. I would expect no less from a teacher of advanced math and calculus.
Where is Mechaniker when you need him?
“Time is based on the rotation speed of the earth with 24 hours equal to one trip around the earth at the equator”
dagosa, please do not try to defend this statement. I know what you meant, that the earth rotates on its axis every 24 hours. The equator is superfluous and there is no way that I could make a trip around the earth at the equator in 24 hours. I don’t think you could either.
Keith…that’s NOT MY statement and I never defended it. I only stated the equator is used as a reference often and why as a response to Littlemouse…who reminds us he can’t read a book and enter fractions in a calculator. That will be.my first and last mistake. But, if I choose to that will be my choice, not yours. The original statement is too incomplete for me to accept either as a definition of the word “time”.
It would be worth while for both you and Littlemouse to read the original post I made on this matter.
…still, somehow, the two of you give me credit for a statement that JosephEMeehan made who smartly avoided getting into this frivolous discussion about nothing. And I’m still not grading littlemouse’s minimal first year Algebra efforts. Plagiarism is seldom rewarded. Littlemouse still pretends he doesn’t get that T=d/v reference is just a relationship between time traveled as a numerical value over a distance d at velocity v. It is NOT a definition of the word time and he and maybe you, conflate the two.
I did not attribute that statement to you, but when you immediately jumped in with your Great Circle nonsense, I did treat it as if it were your statement, as if you had taken ownership of it, and for that I sincerely apologise. Hand behind my back? Oh, just a bit of a cramp.
“I only stated the equator is used as a reference often and why as a response to Littlemouse…who reminds us he can’t read a book and enter fractions in a calculator.”
Again with the ad hominem. Oh well, if you get something out of it I suppose that’s fine.
“And I’m still not grading littlemouse’s minimal first year Algebra efforts. Plagiarism is seldom rewarded.”
Minimal first year algebra was all it took to show the absurdity of your assertion. And your statement begs the question, why would I plagiarize something that’s wrong? I accept your implicit admission that I am right. Second year algebra is for the kids who aren’t going to take calculus. They have to do something.
“Just to answer your other question …time equals distance (circumference) over rate (speed).”
t=d/v STILL just says that 1=1, so what question does it answer? I don’t see how giving me the A+ I earned on that would involve you in plagiarism. And in my day we weren’t allowed to use calculators.
You do your students a disservice if you waste their time with “t=d/v” except as an example of what not to do.
@dagosa…Ignore him…Some people just constantly need attention.