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On December 10 2011 11:10 gyth wrote:Show nested quote +On December 10 2011 10:51 SCJethro wrote:
Alot of those are sort of special cases, So I dont know If I would say we use any other systems, per-say. For example, the use of C in a problem is usually just to make it easier to work through. At the end, C is strill translated to km/h or m/s or w.e., so we still make use of SI. No, if you are making relativistic corrections v is a fraction of c, not m/s. Scientists use SI units, unless it is convenient not to. Strictly metric would be too limiting, but it is a better starting point than "imperial".
im studyin mechanical engineering and had some measurment lectures and stuff.
c is a defined number in m/s
a second is a multiple of the smallest time we can measure (its a frequency of cesium)
now we have an easy equation: V=s/t
solving it: s=V*t
now you take V=c and t=1s/c and you get 1 meter.
you are allowed to do that cuz you defined c and 1s before.
but because thats a long and not rly understandable way, you will just take the meter that you defined this way and take it for granted.
physicians like to use 1c as a measurment unit, just to keep evrything atleast a bit imaginable. but they still use the metric system for calculating, just because its the best system that we have for it.
and btw: my university is working by now on a new definition of the kg. pretty intresting stuff.
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On December 10 2011 11:32 choe wrote:Show nested quote +On December 10 2011 11:10 gyth wrote:On December 10 2011 10:51 SCJethro wrote:
Alot of those are sort of special cases, So I dont know If I would say we use any other systems, per-say. For example, the use of C in a problem is usually just to make it easier to work through. At the end, C is strill translated to km/h or m/s or w.e., so we still make use of SI. No, if you are making relativistic corrections v is a fraction of c, not m/s. Scientists use SI units, unless it is convenient not to. Strictly metric would be too limiting, but it is a better starting point than "imperial". im studyin mechanical engineering and had some measurment lectures and stuff. c is a defined number in m/s a second is a multiple of the smallest time we can measure (its a frequency of cesium) now we have an easy equation: V=s/t solving it: s=V*t now you take V=c and t=1s/c and you get 1 meter. you are allowed to do that cuz you defined c and 1s before. but because thats a long and not rly understandable way, you will just take the meter that you defined this way and take it for granted. and btw: my university is working by now on a new definition of the kg. pretty intresting stuff.
Is the definition based on a certain number of carbon atoms? I believe I heard of that one.
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yeah its just a habbit.
obviously metric is more applicable and useful for math.
obviously you are not going to goto the store to buy 3.17L of paint or milk tho.
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On December 10 2011 11:34 JinDesu wrote:Show nested quote +On December 10 2011 11:32 choe wrote:On December 10 2011 11:10 gyth wrote:On December 10 2011 10:51 SCJethro wrote:
Alot of those are sort of special cases, So I dont know If I would say we use any other systems, per-say. For example, the use of C in a problem is usually just to make it easier to work through. At the end, C is strill translated to km/h or m/s or w.e., so we still make use of SI. No, if you are making relativistic corrections v is a fraction of c, not m/s. Scientists use SI units, unless it is convenient not to. Strictly metric would be too limiting, but it is a better starting point than "imperial". im studyin mechanical engineering and had some measurment lectures and stuff. c is a defined number in m/s a second is a multiple of the smallest time we can measure (its a frequency of cesium) now we have an easy equation: V=s/t solving it: s=V*t now you take V=c and t=1s/c and you get 1 meter. you are allowed to do that cuz you defined c and 1s before. but because thats a long and not rly understandable way, you will just take the meter that you defined this way and take it for granted. and btw: my university is working by now on a new definition of the kg. pretty intresting stuff. Is the definition based on a certain number of carbon atoms? I believe I heard of that one.
the actual definition is just a block that weights 1 kg. you can see it in a museum in paris.
my university works right now on a definition of the specific mass of a certain silicon isotope.
they will get a silicon ball with a specific number of atoms in it (as exact as it can be produced) and the weight of 1kg.
then they will say how many silicon atoms are exactly 1 kg.
--> thats just a number and makes the 1 kg reproducable.
we have our "mass comperator" to help out at weighing it. (we are really damn good at this^^)
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Standard, just makes more sense to do stuff meters etc :p
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On December 10 2011 11:34 ComaDose wrote:
yeah its just a habbit.
obviously metric is more applicable and useful for math.
obviously you are not going to goto the store to buy 3.17L of paint or milk tho.
No, because you always buy it in 3.00L, there would be no reason for the extra parts.
And honestly, I've never heard any American call the Imperial system Standard until now. As said before, I think that's a very US-centric term, and honestly, it's confusing. I like to spend 10 minutes figuring out how many centimetres are in a yard. 
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Metric makes more sense to me I hate standard, been used to Metric for like since I went to kindergarden
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School in metric. Groceries in metric. Thermostat, speedometer, maps, metric. Lumber, hardware, and talking to old people in imperial :/
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On December 10 2011 11:40 Bobble wrote:Show nested quote +On December 10 2011 11:34 ComaDose wrote:
yeah its just a habbit.
obviously metric is more applicable and useful for math.
obviously you are not going to goto the store to buy 3.17L of paint or milk tho. No, because you always buy it in 3.00L, there would be no reason for the extra parts. And honestly, I've never heard any American call the Imperial system Standard until now. As said before, I think that's a very US-centric term, and honestly, it's confusing. I like to spend 10 minutes figuring out how many centimetres are in a yard.
It was named that in the 19th century, when the government standardized units of trade for the US, it has nothing to do with nationalism, its just what the system was called. It slightly differs from British Imperial units, but I agree that it is confusing. The official name I think it goes by now is "United States Customary Units".
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I went to Walmart to print out a photo in dimensions 50 mm x 70 mm. They had no idea. Then I went to their meat section to find the weights in metric.
Oh, Canada.
I like metric system because I don't feel so fat when I weigh myself in kilograms.
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On December 10 2011 11:45 cive wrote:
I went to Walmart to print out a photo in dimensions 50 mm x 70 mm. They had no idea. Then I went to their meat section to find the weights in metric.
Oh, Canada.
I like metric system because I don't feel so fat when I weigh myself in kilograms.
canada switched in the 70's right or something like that i felt it was a pretty recent dealy so i can understand why it's all half and half
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First off, standard and metric are the same thing
I use standard ;P
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I don't know if its been mentioned or where in the discussion we are at. I'm not reading 35 fucking pages worth of (probably) the same argument over and over again. Just want to toss my experience in.
I use metric for everything. Everything. I'm 182 cm tall, 64.3 kg. On my 8.5 km commute to work I average about 33.3 km/h. I usually buy 4L of milk at a time but sometimes I get 500 ml of chocolate milk too. I find 25 degrees Celsius a great temperature and hate it when it gets to -30 degrees celsius in the winter.
The ONLY time I use imperial is in my job. Drill rig augers come in 5 foot lengths. I log soil samples off augers and I have to know what depth they come from. I can count by 5 really easy, and thus just need to know how many augers down we are. Counting by 1.52 sucks balls. Also creates truncation error. So I log in feet. Then when I get to the office I convert everything into metric ASAP using Excel.
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On December 10 2011 11:43 InvalidID wrote:Show nested quote +On December 10 2011 11:40 Bobble wrote:On December 10 2011 11:34 ComaDose wrote:
yeah its just a habbit.
obviously metric is more applicable and useful for math.
obviously you are not going to goto the store to buy 3.17L of paint or milk tho. No, because you always buy it in 3.00L, there would be no reason for the extra parts. And honestly, I've never heard any American call the Imperial system Standard until now. As said before, I think that's a very US-centric term, and honestly, it's confusing. I like to spend 10 minutes figuring out how many centimetres are in a yard. It was named that in the 19th century, when the government standardized units of trade for the US, it has nothing to do with nationalism, its just what the system was called. It slightly differs from British Imperial units, but I agree that it is confusing. The official name I think it goes by now is "United States Customary Units".
Fair enough, but I've always known the system as Imperial, and to see it now stated as Standard is a little irritating, and does initially paint a nationalistic picture in my mind. Thanks for the explanation though.
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On December 10 2011 11:32 choe wrote:
physicians like to use 1c as a measurment unit, just to keep evrything atleast a bit imaginable. but they still use the metric system for calculating, just because its the best system that we have for it.
Calculations work out better in units of c. The binomial expansion of (1-v^2/c^2)^-.5 would be even uglier in m/s.
and btw: my university is working by now on a new definition of the kg. pretty intresting stuff.
Careful not to make it sound too much like a Tennessee senator defining pi as 3.0
The value should stay the same, you're just making a more reproducible method?
P.S. Physicists. Physicians take your temperature.
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2. Standard units are more practical and convenient. No one goes to the grocery to buy 400ml drink, instead, they buy it in 12 ounces. No one buys 5 meters of wood, instead, they buy it is 1x1x12, all in feet.
This just sounds so ignorant. Just because in US you don't use liters doesn't mean that in other countries people don't use them either. Actually in majority of countries you will go and buy 0.5 liter bottles of drink. It sounds super odd to me to go and ask for 12 ounces drink. I have no idea even how much it is.
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Holy shit your handle is "Lebesgue" and your talking in a thread all about measuring.
My mind just exploded.
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Its not standard, its called imperial. Calling the imperial(crap) system standard is an insult. And all measurements in science are by metric, and the metric system makes sense.
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EPT
