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OK..Imagine for a moment that your discussion is pushing a direction you haven't considered. Matter such as protons and neutrons being broken down into smaller particles…the space they take up even though their weight is the same is greater..a force as powerful as a black hole would be strong enough to accomplish this. In turn the increase in space taken ...


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The speed of light is invariable but the number or ratio of the frames of reference are variable as determined by the amount of gravity, the result of which is gravitational lensing.


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Please explain by what means electrons extraction can be done. Hot enough plasmas have all the electrons in the plasma leaving the nuclei positive. How person can focus activity on single atom (from precision point of view) to do so? One cannot deal with individual atoms. It is a statistical phenomenon and one can get a beam of ions without any ...


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Water evaporates if it has a higher temperature and or if the humidity of the air isn't at 100%. This is a nonlinear process as the vapour pressure of water is nonlinear with temperature and the rate of evaporation is linear with partial pressure difference (the partial pressure in the water is equal to the vapour pressure). The evaporation reduces the ...


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The trick is to convert to radians. You're mixing radians and degrees, which I think makes your error too big by $180/\pi$.


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I would reach for an Arduino or similar microcontroller to do the job. You can set the amplitude and frequency of the vibration in code which, in my experience, is always easier than tweaking an electronic circuit.


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This shows a schematic illustration of the Pound-Rebka experiment: At the bottom we have $^{57}$Fe source that emits gamma rays upwards with an energy of 14.4 keV. The frequency of the gamma ray is $3.48 \times 10^{18}$ Hz, but let's just call this $\nu_0$ to avoid messing around with figures. The gamma ray travels upwards, and as it travels it is red ...


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We don't need to separate electrons out in order to observe them. The structure of an atom, as revealed in electron transitions (atomic spectroscopy) is clearly based on orbitals at specific energy levels, with a two-electrons-per-orbital limit. And, the collective behavior of unpaired electrons that gives rise to ferromagnetism, and subtle spectroscopic ...


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Spin was assigned to elementary particles so that conservation of angular momentum would hold in the quantum mechanical framework of elementary particles and nuclei. The Stern–Gerlach experiment involves sending a beam of particles through an inhomogeneous magnetic field and observing their deflection. The results show that particles possess an ...


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Electrons And Spin From Scientific American Unfortunately, the analogy breaks down, and we have come to realize that it is misleading to conjure up an image of the electron as a small spinning object. Instead we have learned simply to accept the observed fact that the electron is deflected by magnetic fields. If one insists on the image of a spinning ...


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The variables in your experiment were : the mass of water in the calorimeter $m_w$ (independent variable) and the temperature rise in the calorimeter $\Delta T = T_{final} - T_{initial}$ (dependent variable). Your equation can be written as : $(m_w c_w + m_c c_c)\Delta T = m_s c_s (\Delta T' - \Delta T)$ $\frac{m_w}{m_s} + \frac{m_c}{m_w} \frac{c_c}{c_w} = \...


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Experimental results can deviate from ideal. Outcomes depend sensitively on small differences in mass and alignment, and the extent to which kinetic energy is conserved. Alignment of non-identical balls is much more difficult. Considerable effort and expense may be required to achieve reliable results. The following sites agree with this view : https://...


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You cut off the sentence that tells you what the numbers mean. "All uncertainties define a 90% credible interval". Crudely speaking, it means that there is a 90% probability of the parameters lying in the quoted range, with the most likely estimate being the headline number. It doesn't really make sense to translate these into Gaussian sigmas (it would be ...


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Q^2 is the Mandelstam variable t, i.e. the four momentum transfer squared where the s channel is the x axis in the feynman diagram. where p1 p2 are incoming. In the same link it is seen that at the relativistic limit : The dot product for t (Q^2) is p transverse to the incoming beam direction of p1 , p2 are incoming. etc. Is this Q the same if ...


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Materials that seem homogeneous often have internal strains, or voids, or even inclusions. Under stress, rather than uniform deformation (bending), those flaws may undergo brittle fracture, or stretch excessively, or become chemically active. A cosmic ray can create internal damage, a particle decay track. So, after some kinds of handling (bending, ...


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The 'formula' is the Principle of Conservation of Energy. Whatever energy (work) is put in via gear wheel 'a' is either dissipated as friction in the gears or bearings, or increases the rotational KE of the gearshaft, or appears as work done on the output from gear wheel 'b'. I assume the gearshaft is balanced so there is no change in its gravitational PE. ...


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Online data analysis is cursory analysis done as the data is collected. It is often used for the purpose of selecting which events to save to disk or tape to be analyzed later (an event "filter"). Given that the current CERN experiments will be taking, in the next run, data at rates exceeding a terabyte per second, this notion is essential. In fact, the ...


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Translations and rotations are not different. A rotation is a general state of motion, and a pure translation is a degenerate form of rotation. In fact a translation is just an indication that rotation occurs at a distance, just as a torque is an indication that a force is acting on a distance and angular momentum is an indication that something at a ...


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Energy lost is due to sliding friction when the gear teeth engage and disengage. Most gears are designed with involute profiles which allow rolling about the contact point when the contact force peaks (at the pitch circle). So the actual energy loss comes from a scrub calculation where the frictional force is multiplied with the scrub velocity to determine ...


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The very flexibility that you mention in your post is a bit of a problem in an experimental context. In order to understand the signal that a Cf-Be calibration source would generate in your detector and tease useful information out of it, you're going to have to model all three channels that generate neutrons and the gammas that escape the source. This means ...


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I don't think there has even been observational evidence of Kerr-specific effects. While gravitational lensing is well known these days I don't think any of the objects studied have been rotating fast enough for the difference between the Kerr and Schwarzschild metrics to be apparent. Well, not in lensing anyway - Gravity Probe B did measure frame dragging. ...


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Typically, we solve a partial differential equation (analytically if we can, but often we can only do numerical calculations), where in the input of the problem we put the known quantities Physics started with observations of nature, and mathematics developed which could model the observations and measurements and predict future set ups. Beginning with ...


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@CuriousOne is approximately right. Others have thought of it, the url below is a paper from one who concludes with slightly more careful calculations (but still relatively straightforward) that the most one could get in terms of a continuous power from it is 50 MW, and typically a lot less. 50 MW is 5% of a large power plant. http://www.electrostatics.org/...


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It is really really really difficult to get a vacuum of 1E-10 Pa at room temperature when surrounded by a 1E+5 Pa atmosphere (sea level on Earth). The answer referring to Penning Traps needs to be understood in the context of the life-time of the antiprotons being on the order of seconds or less. So, unless your story has a method of creating and isolating a ...


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You're not given a long wire and an additional current source to create a magnetic field, nor a permanent magnet, so you'll have to stick with the Earth magnetic field. You'll have to figure out where the North is and whether the North counts as a magnetic North pole or South pole. That's enough to get the sign of the charge carriers and a ballpark estimate ...


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I would use a solenoid. Place two coils above and below the sheet. Something like: You can simply calculate the field strength from the coil radius, number of turns and the current, and you'll get a pretty accurate result. However you need to multiply the calculated field strength by the magnetic permeability of copper.


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You can wind the wire around the cylinder and measure the voltage in the resulting "new" coil as you move it in the field of the Helmholtz coil (say, along the axis - the field is fairly constant in the center, but varies off the center). However, to verify the Faraday law, you also need to measure time. To this end, you may suspend one of the spheres on a ...


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Maybe you don't have to create the magnetic field, you may just use the Earth's magnetic field. As you don't want a complete answer, maybe I should not add anything. Another possibility: you can use a magnetic field of a current.


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The meter will give a value less than what? Less than +300mV or less than -300mV? What voltage reading the meter gives depends on what type it is and what setting is used. Perhaps the book is suggesting that the meter is on an AC setting and will show the RMS voltage. This is $\frac{300}{\sqrt2} mV$ for a sinusoidal waveform, which is less than the peak ...


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Did you notice the caption of the table?


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As you suggested in your comment, the $\mu^-$ and $\mu^+$ that stop in matter do not have the same lifetimes. The $\mu^+$ come to rest between the atoms of your stopper (eg: scintillator?) and decay into $\nu_{\mu}e^+\nu_e$ with the standard 2.2 usec lifetime. However, the $\mu^-$ get captured into Bohr orbits about the stopper nuclei. The $\mu^-$ then ...


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The mirrors in Advanced LIGO are not cooled. Future detectors may utilize cryogenic temperatures to reduce thermal noise, but we aren't there yet.


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This is a physics question and answer site. Laws in physics are a distillation of experimental observations, and a foundation stone in the theories, mathematical models, built up in order to describe data and predict new behaviors. In a very real sense they are the physics axioms that connect mathematical formulae to physical measurements. History of ...


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In reverse order, and to echo CuriousOne's comments, as you know already I'm sure, the second "law" isn't a law, more a general principle regarding the probabilities of the existence of certain quantum states. My biggest question about this is about proof through experimentation. If one were to prove a law through experimentation, what is deemed a ...


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I know that you are explicitly asked about not equipment related answers. But when I learned something from experimental physics then that you should always consider equipment flaws. I could imagine a scenario where the events on which you trigger to start/stop the clock have different rise times depending on where they take place in the scintillator, ...



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