# Questions tagged [unit]

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### 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 ...
• 315
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### 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 ...
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### Engineering calculations in a tool that will handle units [closed]

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 ...
• 422
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### 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 ...
• 275
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### How do you convert "kps" to Pounds per Square Foot (psf)? [closed]

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 ...
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### 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 ...
202 views

### 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 ...
• 133
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### 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) ...
747 views

### 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 ...
• 129
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### 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?
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1 vote
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### units check for horsepower to weight (Hp/W)

is this units breakdown correct: Hp/W= (ftlb/s) / (lbft/s^-2) = s^-1? I think I might made mistake?
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### Convert from RPM to per second [closed]

Is this correct please for my conversion from RPM to per second? I've included my working below: (500 / 60) * 2 * π = 500 rpm to just s-1.
509 views

### How can I calculate the density of air?

I major in chemical engineering, and I'm solving a example of unit operations. The textbook is Warren L. McCabe, Unit Operations of Chemical Engineering 7th ed. Here is example 24.1. And this is its ...
• 103
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### What is pros of weight density?

I've been studying mechanical simulation with nastran/patran, nowadays. I knew weight density is used in imperial unit system, instead of mass density. I feel using weight density is tedious, ...
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### Unit conversion error - Darcy Radius of Well Influence Equation

I'm having a little trouble. I'm trying to convert the answer from imperial to metric but can't seem to get the answer to match. I am using the formula attached (Darcy Radius of Well Influence ...
83 views

### Thermal conductivity listed in the rather complicated Btu/s-in.²-°F/in - am I converting this right?

I'm currently working through some rather old documentation which gives the thermal conductivity of a material as 9.8 x 10⁻⁶ Btu/s-in.²-°F/in. There are many typical ways to give a thermal ...
• 103
47 views

### I need clarification on how pressure is measured

I have a vessel that has a pressure measuring device. The value it shows as the pressure inside the vessel is 6 inches of water column. Is inches of water column meant to always be used as gauge ...
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### Converting flow rate from normal/standard liters per minute to cubic meters per second

I'm really confused about these three units commonly used for measuring airflow: cubic meters per second (m3/s) normal liters per minute (NLPM) standard liters per minute (SLPM) I would appreciate ...
• 259
42 views

### Fundamental error when assuming "per unit Celsius" = "per unit kelvin"

While doing a chemical engineering question today, I came across something quite fundamental that I can't seem to get my head around. I had a value in bar/°C, and I had to multiply it by a temperature ...
42 views

### General Units question

so let’s say I worked out a quantity that turned out to be unit less but to work it out I used pounds (lb) and feet (ft) and the units cancelled out But then I used this unit less number later in ...
69 views

### Unit of blower speed

I want to know whether the international unit of blower speed is RPM or r/min. I konw ther're the same, but I'm not sure which one is more prevailing internationally. Thanks for answering.