# Tag Info

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That is a naming scheme of National Electrostatic Corp. (NEC), and is likely trademarked. The number has to do indirectly with the maximum terminal potential. Their website (pelletron.com) has more info. Not employed by NEC, long time user of their machines (and many others).

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A basic question is - how hot does a bullet actually get? Here is an answer. Note that the biggest effect is frictional heating in the barrel lands, which produces peak temperatures of ~320 C. Also note, though, that the affected areas are quite small in proportion to the overall bullet size, so the average bullet temperature rise is also quite small. ...

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Assuming that the bullet flies at Mach 2.0, the temperature at the front of the bullet is about the same as the surrounding air (since at that relatively low Mach number, there is little thinning of the boundary/shock layer to cause aerodynamic heating). I do not know how much heating there is from the gases in the chamber/barrel (it may be significant, but ...

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Since the question is "can you recommend a book that talks about these topics with minimal math," the answer is no. It would be even more confusing to describe quantum information and quantum computing without math than with the math, as the concepts aren't as intuitive as say general relativity, which can fairly effectively be described with mostly words. ...

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It can vary widely. In the US, undergraduate physicists are expected to take math classes including: Calculus up to Multivariable Calculus Differential Equations Linear Algebra They also often take a class in mathematical physics that covers things like advanced integrals, contour integrals, gamma functions, special functions (Bessels, spherical ...

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Current trend today in MBD is towards writing code, doing simulations for some practical problems. That is not entirely true and it mostly depends on the actual areas and topics you are dealing with, as for all the other subjects. Of course, due to the industrial applications, the practical side always has more money and more academic positions, but ...

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I'm not sure what might be confusing you. Assume, as in most cases with the Golden rule, that the transition rate is constant, $\Gamma$. So, for small times, the cumulative transition probability is $W=\Gamma t$. Think of the transition as leakage from a vessel. At $t=0$, no water has been lost, but with a constant rate of leakage, $\Gamma$, the longer ...

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The Parks College Parachute Research Group did some really interesting testing in the late 1990s about the opening profiles of various parachutes. One interesting fact (as an aside) is that smaller chutes actually decelerate you with up to 40% more force. They also published a series of force-load profiles during opening, examples of which can be seen ...

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So, even though they are measured in grams (which you correctly assessed as a unit of mass), it is quite all right to call these objects weights. That is because the word weight can refer to the force of mass times acceleration due to gravity or "a body of determinate mass." (dictionary.com)

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If you pick up a weight and bring it some other place, then the weight at that other location will not be exactly the same. Wat happened to the difference between the initial weight and the final weight? Because weight it is not conserved, nothing needs to have happened. If you had instead said that you picked up a mass and brought that mass to that other ...

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It is absolutely fine to call these objects "weights", since you are interested in their weight - i.e. the force of gravity on them. You are not using them for their inertial properties. Dictionary definition of weight: (Dictionary.com - definition 5) a body of determinate mass, as of metal, for using on a balance or scale in weighing objects, ...

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Actually, any planet $X$ can be see to transit the sun from any other planet $Y$ with a larger orbit. That being said, the frequency for which the a particular transit happens tends to decrease as the planets you choose are further away from the Sun. For example, here on Earth, the angular diameter of the Sun is about 32 arcminutes, or just slightly more ...

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It means that both neutron shell and proton shell have been filled. Neutrons and protons have different isospin values, hence they can have all other quantum numbers equal. This means, in the context of Shell Model, that they will occupy different shells and the filling of neutron shells is independent from the filling of proton shells. Hence when a ...

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They open as text files after you unzip them. You can open them with excel to parse the data

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(I presume that you meant "Physicist" not "Physician" as in one who practices medicine) Scientific theories are usually a group of ideas that are linked either through a common phenomenon or a common method. Usually, for more developed theories, these are in the form of postulates(think of quantum mechanics or statistical mechanics), with other ideas ...

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The Hilbert space formulation, sometimes with the explanatory add-on: "where observables are represented by linear operators acting on Hilbert space". Both the wave and matrix sub-formulations are basically shadow-double formalisms for the very same structure.

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