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### How to derive velocity pressure in English units?

I know that velocity pressure can be calculated from dynamic pressure according to the potential energy of pressure (from Bernoulli's equation): $$P = \frac{1}{2} \rho \overline{V}^2$$ where P = ...
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### Geometrised Units

I am curious as to how to express a area units in geometrised ones. I was reading on wikipedia and saw that when angular momentum is converted into geometrised units, it is expressed as a dimension of ...
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### Noise of a fiber optic gyro

I have not much experience with noise handling or calculations, furthermore in my researches couldn't find a similar problem, so here is my attempt: Having a fiber optic gyro that is rated with a ...
I need to convert this expression $81752 \left( \frac{BTU}{in^2 h ÂºR} \right )$ to $\left( \frac{Kg}{s^3 ÂºC} \right )$ Is my draft correct? $81752 \left( \frac{BTU}{in^2 h ÂºR} \right ) \... 0answers 192 views ### Galaxies and projected radius vs arcmins I have two sets of data (globular clusters), one for the Andromeda Galaxy and one for the Milky Way. I want to compare the distribution of globular clusters between the two galaxies according to ... 1answer 532 views ### noise level (units confusion) i had a question in one of my classes regarding SNR in underwater acoustic channels. There are a couple of terms with the unit dB re uPa. I know it stands for dB ... 0answers 1k views ### FPS to MKS usage issues I'm currently taking a high school physics class and we're doing friction problems now. I've been doing the ones that use MKS perfectly well, but when the problems start to use the FPS system, I'm ... 8answers 7k views ### Celsius to Fahrenheit confusion: why there is no 1 to x ratio? Why is it not possible to know the ratio of 1Â°C to how many Fahrenheit and use that to convert from or to Celsius/Fahrenheit? What is really happening? Fahrenheit increases linearly and so does ... 3answers 545 views ### 100°C = 100 K =? I'm in first year. Our class is in lesson " Heat and Thermodynamics". While solving a numerical problem of a reversible engine he told us that 100 degree Celsius is equal to 100 kelvin. I inquired but ... 2answers 2k views ### Why does$E=mc^2$give results in Joules? Why does$E=mc^2$give results in Joules ? Why didn't Einstein need to create a separate unit and how come using two standard units (speed of light in km.s and mass in grams) give another result in ... 3answers 135 views ### Proper way to write the units to indicate that they include an offset? Past a certain point of complexity, I get rather confused with physical units, so I am asking a physicist for help. I have a code that represents temperature, with a resolution of [0.5 Â°C], whose ... 2answers 100 views ### What is$c$in the Lorentz force expression? The usual Lorentz force expression I am familiar with is this: $$\vec F=q(\vec E+\vec v \times \vec B)$$ I have seen some other versions lately that include an extra factor$1/c$: $$\vec F=q\left(\... 2answers 194 views ### How many psi's are in one bar? 6894.7573 bar = 100000.0 psi according to google 6894.7573 bar = 100000.0001 psi according to wolfram alpha which is it? How many psis are in one ... 3answers 70 views ### Displacement based on acceleration in km/h^2 For calculation of displacement based on acceleration and time, I have the formula below:$$ x = v_0t + \tfrac{1}{2}at^2 .$$If I get a in km/h^2, and x in km and v_0 in km/h and I suppose ... 1answer 5k views ### How does (kg/m^3) * (m/s^2) * (m) come out to be units of N/m^2? [closed] To me it seems to come out to be kg/(m*s^2). Is this somehow equivalent to N/m^2? 6answers 65 views ### The Kelvin-Celsius problem Let's suppose we have temperatures 30Â°C and 35Â°C. Converting them to Kelvin we have 303.15K and 308.15K. In the second case, the temperature difference is 5K. While in first case, temperature ... 1answer 82 views ### Converting F^2 to C^2 I'm trying to convert Fahrenheit squared F^2 into Celsius squared C^2. I know how to convert a value x in F into C with: \frac{5}{9}(x - 32) I also know how to convert a value x in ... 1answer 244 views ### Dimensional Analysis in Electromagnetism (SI vs Gaussian-cgs) Looking at Konopinski's formula for conjugate momentum (in the comment after equation 3 of "What the Vector Potential Describes"): p = M v + q A /c it is plain enough that M v is momentum, but if we ... 2answers 57 views ### Significant error conversion So here is my question: Say we have measured something to be 15,67 mm and the significant error is \pm 0,01mm. then we convert the measurement to meter to be 0,01567m would the significant error ... 1answer 3k views ### I need some help trying to convert the specific fuel consumption from imperial to metric units Ok the imperial unit for the specific fuel consumption for a jet aircraft is shown below. Its the amount of fuel (in lbs) per hour required to produce 1 pound of thrust.$$\frac{\frac{lbs}{h}}{lbs}$$... 1answer 450 views ### if a force is 1 newton metre, what is it at 2 meters? If I have a force, say 24 kg/cm what would that equate to at 2cm? I would like to know the formulae for calculating this. For example. If a motor can hold an object of 24kg at 1cm from its pivot ... 2answers 46 views ### Confusion on electron volt and Kelvin? If an element A has a binding energy of X eV with element B, can it be said that it is equivalent to X*11600K as 1 eV approx equals 11600K. I do not think this is correct as temp. is linked to the ... 1answer 47 views ### Fine structure constant and unit conversion [closed] In a paper I'm reading, the author writes down the following formula:$$\Gamma=\dfrac{\alpha^2}{576\pi^3}\dfrac{\left(4+z\right)^2}{z}\dfrac{m^5}{m^2_\pi f_\pi^2}$$\Gamma is a function of m (in ... 1answer 36 views ### Classification of plane angle as fundamental or derived I recently started with my high school studies and the chapter I am stuck at is units and measurements. I was told about two types of physical quantities and my teacher gave me the following ... 2answers 55 views ### Bohr's model and positronium I was trying to get an order of magnitude estimate for the radii and energies of positronium using the Bohr's model. I did find a few places where they have used the reduced mass to replace the ... 2answers 271 views ### If a propane torch is rated at 200,000 BTUs, what does this translate to in terms of joules/second? If a propane torch is rated at 200,000 BTUs, what does this translate to in terms of joules/second? Not exactly a physics question per say, but it falls in the realm. How do I convert/understand ... 1answer 64 views ### Constant c in Lorentz force [duplicate] I met some of examples of force in studying classical dynamics, and Lorentz force was represented as$$ \mathbf{F}=\frac{q}{c} \mathbf{\dot{r}} \times \mathbf{B}$$I've searched for meaning of$c$, ... 1answer 93 views ### A Conversion problem featuring Significant figures [closed] What is the speed of a car going v=1.000 mile per hour in SI units? You can do each conversion separately. Use the facts that 1mile=1609 meters and 1hour=3600 seconds. Express your answer in meters ... 2answers 332 views ### Unit conversion from km to mm [closed] I'm a bit rusty on my unit conversion skills and I need help figuring out what I did incorrectly converting 9.06 x 10^8 km into mm. Here's what I did: 9.06 x 10^8 km x (1 meter/10^3 km) x (10^-3 km/1 ... 1answer 171 views ### Magnetic Field and the Speed of Light Is it just a historical choice that both magnetic field and the Lorentz force equation include the speed of light? I figure that whoever wrote up the equations (in cgs!) could have put both factors ... 1answer 740 views ### CGS Units to SI Units This may be a stupid question but I am having trouble getting the same result in CGS units as I would if I used SI units for a unitless calculation. I have to calculate$E_c=\frac{m_e c\, \omega_c}{...
In a paper I'm looking at and also in a similar program, the authors note that the nuclear radius $R$ is given in "natural units" as $R = 3.11\times 10^{-3}\;A^{1/3}$. This has me slightly confused, ...