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Ignore the diagram. It's complex because it includes all the various bits of electronics required for the experiment and that confuses the issue. The experiment is just a variant of Mössbauer spectroscopy. The experiment uses a $^{57}$Fe source that emits a gamma ray with an energy of 14.4 keV. Since this energy matches the spacing in the energy levels of ...

4

I like that this question is asking for some intuitive justification and calling for more understanding in error analysis. Too often, that's left out. From a teaching perspective, I think what's most important is that students come up with their own procedure, that's it's reasonable, and that they justify it. This encourages them to do the same sort of ...

4

There have been lots of experimental attempts to test the validity of Coulomb's $r^{-2}$ law. Many of these are reviewed by Tu & Luo (2004), and is where I am getting the numbers quoted below. Somewhat equivalently, experiments have looked at trying to set an upper limit to the photon mass, which is testing the hypothesis that rather than a $r^{-1}$ ...

3

As it turns out, Luis Alvarez was famous for his notes/memos, and Lawrence Berkeley Laboratory (the successor name for the Radiation Laboratory) has been kind enough to put them all online at Alvarez Physics Memos. Search for memo 470 and you will get a pdf back that includes 'Design of an Electromagnetic Detector for Dirac Monopoles'. The 10 in that pdf are ...

3

An 8" telescope was state of the art in 1686 (even though a modern amateur instrument is certainly much better than Huygens' lenses were) and a normal DSLR sensor has only slightly better properties than plates that were used in astronomy up to the 1980s, so there isn't much gain there, in terms of instrument performance, over fairly old equipment... it's ...

2

Background There is a good reference1 on the physics of sound/shock waves in solids (look at Chapter XI). I found the following (on page 688) very interesting and relevant to your question: In a solid or liquid, a shock wave with a strength of even a hundred thousand atmospheres is regarded as weak. Such a wave differs little from an acoustic wave: it ...

2

There are several broadband light sources in outer space such as quasars and blazars which basically can act as a light bulb. Earth bound telescopes as well as satellite telescopes can see absorption features in the light when the light passes through some cloud in outer space that contains molecules before the light reaches earth. In addition molecules in ...

2

Are you using the Apex-Gamma software? If so, a fitted singlet is a line the software has identified as being a single distinct line rather than a peak in a region where there are multiple overlapping lines. As I recall, Apex-Gamma identifies lines that are overlapping by $M$ or $m$ (presumably for multiplet).

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I gather that the large source of error you are worried about is the ability of the experimenter to accurately hit the start/stop button on the stopwatch at the start/stop of the ball's journey down the ramp. What is the approximate magnitude of error we'd expect? Before I directly answer your question, let's estimate how bad the experimental error will be ...

2

Coulombs law as well as Amperes law and similar mathematical formulations of two centuries ago, were incorporated within the strict mathematical format of Maxwell's equations . The apparently disparate laws and phenomena of electricity and magnetism were integrated by James Clerk Maxwell, who published an early form of the equations, which modify ...

2

Bohr's atom became famous for reproducing the Rydberg formula for spectral lines of hydrogen, which Rydberg presented in 1888 and published the next year. Bohr remarked that it was Rydberg's switching from wavelengths to wavenumbers that allowed him to make the discovery. His inspiration came from Balmer's 1885 formula, which was a particular case, and had ...

2

The definition of "Heat" is energy transferred due to thermal contact. We know hot things cool down when they touch cold things, and cold things heat up when they touch hot things. So, that means the hot thing has to be losing energy, and the cold thing has to be gaining energy. That means that heat is flowing from hot to cold.

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It would be theoretically possible, but not with magnetic fields [n.b. the word in English is "field"]. The problem with magnets is that they are always dipoles so have a North and South pole. If you jumped with your head a South pole and had South poles on the floor, the slightest imbalance would flip you round and pull you down faster than gravity. If you ...

1

I might be erring something basic here, so downvotes are welcomed, but I would love if they include comments to correct this answer, or just erase it. I do not believe the Coulomb law has been tested beyond the order of a few meters. Arguing that light remains unchanged across the universe should be irrelevant. The reason is that the electrostatic and ...

1

A good starting point would be the series of papers by Bohr, starting with "On the constitution of atoms and molecules" Philos. Mag. 26, 1 (1913) and checking the references therein.

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You don't explain what you are doing in the experiment, but I would guess it is supposed to demonstrate conservation of angular momentum. If we calculate the angular momentum $L$ using: $$L = I\omega$$ then unless some external force is applied $L$ will be a constant. When you start the experiment the disk has moment of inertia $I_\text{Disk}$ and is ...

1

the answer is no: for now there is a high correlation between the properties of planets (size, distance to their star) and their probability to be detected, which totally bias the observed distribution.

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That means that the peaks could be fit with single Gaussian, the simplest fit. They did not have to fit as a doublet (two lines close together). Ortec has a technical paper on line at Deconvolution of Gamma-Ray Peak Doublets as a Function of Peak Separation and Relative Amplitude

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In addition to CuriousOne's fine answer, I'll point out that Dobsonians, while easy and cheap to build, are rather difficult to combine with a tracking mount. For really good photos (or faint objects), you'll be much happier with a slightly more expensive 'scope with an equatorial mount and a USB interface to your PC. In general, don't bother with an ...

1

The gaussian normal distribution is a good guess when you don't know anything else, due to the Law of Large Numbers. If you know more about the process that generates the measurements, then you can choose another distribution. For example, if there is a lower bound on measurements, (for example: concentrations of a chemical compound in blood plasma cannot ...

1

The normal distribution has a very important special role in stochastics. One can prove mathematically that the distribution of the sum of many independent statistical processes is almost always a normal distribution. This is called the "Central Limit Theorem" in mathematics (there are actually several of these) and you can test it very easily yourself with ...

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