# Tag Info

21

You are probably right (it being of Russian origin). The weight seems to be 5 funt. 1 funt is the Russian equivalent of a pound. It is written as Фунт, funt, and around 1900 it was the basic unit of weight measurement in Russia (so it survived in the USSR days), but now its obsolete. 1 Φ is about 409.5 grams.

11

For most of China's history, a system of decimal time was used along side duodecimal time. As part of the Metric System, the French tried to introduce decimal time, where 12 duodecimal hours would be replaced by 10 decimal hours. In 1998, the Swiss watch company Swatch introduced a system of decimal time called Internet Time, where 1 day is divided into 1000 ...

11

In European culture, hours have been used as the basic time interval since time immemorial. You will find a substantial amount of useful information on the relevant Wikipedia page. However, until the universal adoption of mechanical timekeeping, hours were "unequal", defined as 1/12th part of the day or night with the length varying throughout the ...

9

I 'll start with the one that you should DEFINITELY NOT use: $mm^3$ or $mm3$. Probably the most widely used is the 1st. It's compact and economical and these are two of the most deciding factors in Engineering thought and practice. To take the point one step further, if it's in an engineering drawing you don't even need to put units in. Unless, its ...

9

100 cN.m are 1 N.m The c before the N.m is pronounced centi. It's a standard SI prefix. 1 c of a unit is $\frac{1}{100}$ of a unit. Therefore to convert toN.m you need to multiply cN.m with 0.01. $$0.01 \text{N.m} = 1 \text{cN.m} =1 \text{N.cm}$$ Probably the prefix centi is most commonly encounter used in centimeter cm. Regarding the uses of cN.m or ...

7

You can use any consistent set of units. That includes SI. But if you try to use a pressure in ATM, a sphere radius in feet, a wall thickness in mils, and want the stress in tons per square inch, you will probably get the wrong answer that you deserve!

7

Judaism has a long history of tracking both days and times. Most of this is centered around Jewish holidays, particularly the need for Passover to take place in the spring. The basic date measurements are the day, lunar month (basically alternates between 29 and 30 days) and the year. The year is measured as a combination lunar/solar year, approximately 354 ...

6

In an earlier comment, I suggested that an answer to "what is the correct way..." (as opposed to "What is the generally accepted way...") might be found in the ISO 80000-3 standard. I had a look, and there's nothing relevant in ISO 80000-3. Nor can I find any other ISO standard that explicitly states a correct way of doing this. ...

6

We cannot obtain negative temperatures in thermodynamics calculations. Only the absolute scales prevent this. The two absolute scales are Kelvin and degrees Rankin. Here are the two calculations to show that both give the same result. I take that $r^{k-1} = 3.45$ based on using your Rankin values. $$T_f = (50 + 459.67)(3.45) = 1763\ ^o\mathrm{R}$$ $$T_i = ((... 5 There are many possible culprits. One of them is the following. Check in the lower right corner of your Solidworks window. you should see if you click on it, you should see the following menu. You might have pressed it accidentally. 5 N/m or Nm^{-1} is the correct unit of a spring constant and it's already in SI units. Nm or N*m on the other hand is the unit of a torque (or moment) and is also in SI units. So no, Nm and Nm^{-1} are not the same at all, they measure very different things. Similarly, Nsm^{−1}, Nsm and Nsm^2 are all different units of different dimensions to measure ... 5 Weight is a force and is expressed in Newton (N). Mass is expressed in kilogram (kg). However, in informal (non-scientific) language, people often express weight in kg, although this is not correct strictly speaking. The relation between the two is F=mg, with F the weight (N), m the mass (kg) and g earth's gravity constant. See also here. 5 TL;DR: the MM in MMtoe is probably related to the Latin Numeral M (for 1000). In that context MM means one thousand thousands (i.e. one million) Although this is very confusing, the bottom line is that to (my understanding)$$ 1 \text{ MMtoe} = 1 \text{ Mtoe} = 10^6\text{ toe}$$Where: 1 toe = 11.63 megawatt-hours (MWh) 1 Mtoe = 1 MMtoe= 11.63 terawatt-... 4 Strength can mean different things in different contexts and technical definitions can vary significantly from what is commonly understood by the word 'strength'. For structures where actual forces are more relevant you might talk about rated loads, safe working loads or design loads in conjunction with factors of safety but this usually needs to be ... 4 First Part Simplifying the$$ 1 \ lbf = 1 \ slug .ft/sec^2 $$then$$ 1 \ lbf \ sec^2 / in^4 = 1 \ (slug .ft/sec^2 ). (sec^2/in^4) = 12 \ slug /in^3  12 \ slug / in^3 * (14.6 kg / 1\ slug)*(in/25.4 \ mm)^3 = 0.0107 \ kg/mm^3 $$Note that that each slug equals to 14.6 kg so (1 slug / 14.6 kg) equals to 1.0 and any expression multiplied with 1.0 will ... 4 A non forgotten alternate variety of time is Unix Time, https://en.m.wikipedia.org/wiki/Unix_time which ignores leap seconds, and as such is slowly drifting away from UTC 4 To my knowledge when you are doing thermodynamic calculations you should always use K (Kelvin), unless stated otherwise in the textbook you are using. Otherwise the results from those relationships (with powers) will always be all over the place. Another way to put it (probably more correct) is, "Always use the units in the textbook. When in doubt use ... 3 Depends on the culture and civilzation. The romans had their civil day which had numerous subdivisions. See the wikipedia article below. https://en.wikipedia.org/wiki/Roman_timekeeping#Civil_day Monasteries had their own "canonical hours" https://en.wikipedia.org/wiki/Canonical_hours I'd imagine most people would just look at the sky to know what ... 3 There are seven fundamental SI units (seconds (time), metres (length), kilograms (mass), ampere (current), kelvin (temperature), mole (amount of substance) and candela (luminous intensity) - https://en.wikipedia.org/wiki/International_System_of_Units. There are a bunch of derived units and acceptable prefixes (for orders of magnitude) (see that Wikipedia ... 3 I've done some searching, according to this converter kps or KPS stands for Kilo Pascal, but don't use that abbreviation. The actual abbreviation for Pascal is Pa, and for kilo a small k, combined kPa. Thus:$$ 1\hspace{1mm}\mbox{psf} = 47.88\hspace{1mm}\mbox{Pa}  With that assumption, are your values in a reasonable range? I assume that kips in the ...

2

For your question, 1 m2 = 10^12 Darcy. For the next question, I think your question is units involved in Darcy's Law, i.e., the Darcy's units and SI units. In general, we define the permeability of porous media as 1 Darcy, it means the porous media can transmit 1 cm3/s of water with viscosity of 1 cP (1 mPas) under pressure gradient of 1 atm/cm cross an ...

2

The term "English Units" might be confusing, especially with the English and American... I believe the term is "Imperial Units" for those in the UK, but not sure how other countries refer to them. Gallons are defined as US or Imperial and have different volumes. But a gallon does have different volumes in history anyway... Inch-pounds is a "standard" name,...

2

50μm → 0.002" or 2 thou or 2 mils? I've seen both 0.002" and 2 mils. On a drawing it would always be 0.002". In a specification document it could be either. I've never seen 2 thou written in a formal specification (but I have heard people say it in the shop). But that might just be my experience. There could be variation from industry to industry. Is ...

2

If you're interested in using Python, check out the pint, astropy.units or unyt packages. I have personally used pint + jupyter for day-to-day engineering in the past, and have looked at the others and they all should be suitable.

2

1x2x3 mm is usual. You might specify individual units if they used different multiples. For example, if you had a large sheet of thin material you could describe it as 1 m x 2 m x 3 mm. However in metric engineering drawings it is common to keep everything in mm and describe this as 1000 x 2000 x 3 (with a note in the corner of the drawing stating all ...

2

The half life of Radium 214 is 2.46[s]. You can check half times at the following wikipedia article. I am not sure what the 3 stands for, but I suspect that this is some sort of annotation/footnote that was not properly inserted in the webpage.

2

If you are referring to the article A Structural Battery and its Multifunctional Performance then the dimensions appear to be incorrectly written. Structural Battery Full Cell Preparation (Section 4) An illustrative overview of the structural battery composite full cells manufacture is shown in Figure 1. The negative electrode was made from a CF spread tow ...

1

If you have defined the same units for v and c then the equation should work just fine. In all likelihood, h is the probability density so you its units should be $\frac{s}{m}$ In order to see where the problem lies, I would suggest breaking up the terms and checking their units independently within the software. I.e. I would find the units in EES for: \$\...

1

In ancient India, multiple hindu texts have measured time (kāla, which is eternal) ranging from microseconds to trillions of years. Some of these texts date back as far as 2nd millennium BCE. For example, Rig Veda - oldest known Vedic Sanskrit text - gives base / smallest unit of measurement as Paramāṇu (परमाणु) which is ≈ 25 µs. Longer measurement of time ...

Only top voted, non community-wiki answers of a minimum length are eligible