Questions tagged [unit]
32 questions
16
votes
1 answer
What unit of weight is that?
Recently I was weighting stuff with my dad and as I was playing with one of the old 2 kg weights I felt with my fingers number "5". After cleaning and upon further inspection it turned out the writing on the weight says "5Φ". We checked and it…
elementiro
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10
votes
7 answers
Forgotten time units
As my kids are counting down to Christmas, I came to wonder how did people measure time through history. More precisely I wonder about unit systems for precision time keeping of years past gone.
I am wondering this, because the other two most…
NMech
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5
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6 answers
Engineering calculations in a tool that will handle units
I know Mathcad handles units along with numbers which makes it easier to avoid errors by tracking units the way we would by hand.
e.g. 250 kW + 500 W
I just wanted to compare tools before I switch to Mathcad. Are there any other tools people are…
curious_cat
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4
votes
1 answer
What does MM prefix mean in MMtoe?
I was reading documents about energy importation and came across the following:
The import was of 5,915.87 MMtoe
I wonder if MMtoe = $10^6*10^6$ toe = $10^{12}$ toe.
First time coming across a unit expressed like that.
RSM
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4
votes
1 answer
How do you convert "kps" to Pounds per Square Foot (psf)?
I'm looking at a soil bearing capacity report, which has a column labeled "kips" and the values are followed by "kps".
A "kip" is 1000 pounds, but I'm not sure how to convert from "kps" to psf.
The data has values in the 17 to 45 kps range. If I…
Nick
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3
votes
1 answer
What mathematical operation should I do in order to translate from TWyr/y to TWyr_30 in this article?
In this article
https://www.sciencedirect.com/science/article/pii/S266711312200002X
the authors show a result of prediction on energy reserves (in particular solar ones) as known in 2015 (Figure 1) and as known in 2022 (Figure 2).
In the first one…
Mathieu Krisztian
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3
votes
2 answers
Unit of "cN.m" used on torque wrench
I'm using a torque wrench whose unit is cN.m. I wonder what unit this is, and how to convert N.m (Newton meter) to cN.m.
user33290
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3
votes
1 answer
Unit Conversion for Mass Density
I am doing a Finite Element analysis of a continuum. In my problem definition I use these units:
mm for length, kPa for applied stress, and MPa for material stifness (Young's modulus).
With these units, I get my output in: kPa for stress and…
Fritz45
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2
votes
6 answers
What is the accepted way to write units when specifying multiple dimensions?
When writing out dimensions in the form height x width x depth, what should you write for the units? For example, I can think of a few ways to approach this (assuming each dimension is measured in…
JolonB
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2
votes
1 answer
How to set measure display units in Solidworks drawing?
I have already set millimeters in document propertis, nevertheless the display units are meters
Why and how to fix?
Dims
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1
vote
2 answers
Strange units with UV water disinfection systems
When retrieving information about UV systems for water disinfection I frequently encounter minimum intensity values.
e.g. here: Basics of UV disinfection, page 23
All those I find are given in a unit I do not understand.
Frequent value for…
Ariser
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1
vote
2 answers
Inconsistencies with units for thermodynamic identities
I am working out the temperature for an Ideal diesel cycle:
Based on the isentropic properties for an ideal gas.
$$T_f = T_i * r^{k-1}$$
Where $T_i = 50 ºF = 510ºR$
If I use ºF, then $T_f = 172.9ºF = 632.9 ºR$
If I use ºR, then $T_f = 1763 ºR =…
RSM
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1
vote
1 answer
Weibull distribution Units - ENGIEQSOL
I am using Engineering Equation Solver, and it has been telling me the units of my distribution are inconsistent.
According to a the book I am reading, I think it should be unitless (as it is a probability).
However EES, says
$$ h =…
RSM
- 271
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1
vote
2 answers
Questions about newton metre units
I have a few values in Newton metres and I need to make sure each value is an SI unit for calculations. However when I try to search for the units I am given, I can only find similar, but not quite the same, units.
Can someone help clear up the…
MendelumS
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1
vote
1 answer
US customary units below 1 mil/thou?
I have been asked to provide some of our technical docs in both metric and US units. For the most part, that is easy enough:
approx 1cm → approx 1/2"
500μm → 0.02"
But then I start getting stuck:
50μm → 0.002" or 2 thou or 2 mils? Is there a…
Jack B
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