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The difficulty of the prior experiments consisted in isolating the relativately weak gyro magnetic effect against the background of the purely magnetic forces acting on the studied rod... In order to avoid this difficulties, in the variant of the experiment proposed by Einstein, the magnetic field of the coil acts on the iron rod ... for a very short ...

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Fibre fineness is the mass per unit length. To get an accurate number you should measure this directly. But as an approximation, you can look up the density $\rho$ of the relevant fibre, and you have measured the diameter $d$, so the fineness is $$f=\rho \pi d^2 / 4$$ In the case of hemp, you have $d=86.28\times 10^{-4}$ cm and $\rho=1.25$ g/cm$^3$ ...

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In the abstract of this article Measurements of environmental background radiation at location of coal-fired power plants (PubMed, 2004) the terms are used in context. "Zero background radiation" - is the natural expected radiation measured far away of the specific pollutant site - the coal mine. It is a control or reference value in the study. ...

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In physics, fundamental particles are typically treated as point particles. In this approximation, they have no size or shape whatsoever. They sort of have a location, but we can never exactly pinpoint this location in space, because quantum mechanics tells us that a particle never has an exact location. The classical model of the electron does yield a ...

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... smith may use what is called a "dead blow" hammer to reduce the rebound. Thus, measuring the force is not just a question of the instantaneous force of the hammer, but how much it "presses" after that first instant, its impetus so to speak. Now, one idea I had was to use a teeter-totter They are not good solutions. The dead-blow hammer in ...

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According to Quantum mechanics a particle exists in a state $|{\Psi}\rangle$ which belongs to a hilbert space of states. When you make a measurement, you act on the state with an operator, say $A$. And by doing this you project the state $|{\Psi}\rangle$ onto the subspace spanned by the eigenvectors of $A$, so now your state is one of the eigenvectors of $A$ ...

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No a measurement doesn't have to change the state of the system, but it has to at least has the possibility to change the apparatus; otherwise you wouldn't call it measurement. The change to the environment(the apparatus , the scientist and everything that interact with it) is what cause you to lose interference pattern. This is usually called decoherence ...

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Does the measurement of the particle change it's physical state? A measurement, as an evaluation of given observational data, does not have any direct physical effect other than being accompanied by a change of state by whoever carries out the evaluation; the state changing from not yet knowing the result value (or indeed whether one could be obtained ...

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As noted by Floris, the best way to measure small-value resistance is to use a four-point Kelvin connection; unless the current drawn by the voltage meter is significant (in which case there are other problems) then provided that current-source probes are either the inner two or the outer two (as opposed to being interleaved with the voltage-reading ones) ...

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Short answer - yes, everything in the circuit can contribute. But usually, an ohmmeter is zeroed with the probes in place - in other words, whatever resistance the probes represent is taken out by the meter. There are two other factors that play a role, especially when you try to measure small resistance. The first of these is contact resistance: it is ...

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"Which reading is correct?" That is called measurement uncertainty and that's why we have people called metrologists. Is there a naturally occurring phenomenon with a known sound pressure level to which we can compare a sound pressure level meter's reading? Probably not, at least not any practically feasible one at the current level of technology. ...

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The double slit experiment basically shows these results, which is quite extraordinary in my view. If an electron is fired from a gun one at a time towards a double slit, we will see interference pattern (vertical bars), which kind of shows what water wave will show if it hits a shore for instance. Because of interference, some systematic areas on the board ...

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Quantum mechanical entities are described by solutions of the Schrodinger equation, the wave function, with specific boundary conditions. A measurement changes the boundary conditions and thus the subsequent wavefunction describing the particle measured will be a different one. A measurement picks an instant from the probability distribution describing the ...

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you can use GOM playef pres F to count revolutions if you count 6 frames per revolution 6x5= 30 frames then you spin is 5 rev per second thats is tha same 5x60 second= 300 rpms, or use iphone Spinorama free app

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I'm not an engineer, but this is how id do it. According to your rules, we can use a computer, and Audacity. You get a pair of headphones. You plug the headphones into the microphone jack on your computer. You open Audacity. You get a very small magnet. You glue the very small magnet to one of the fan blades. You turn the fan on. You hold one of the ...

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You will get a pretty good answer by reading this paper. In short: fat, water, and muscle each have different electrical properties as a function of frequency. By measuring the (very small, on the order of micro amps) current that flows between your legs when frequency of the driving voltage is changed, you can create a model of the body as parallel and ...

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