Questions tagged [experimental-physics]
For questions about design, process, data, or analysis of experiments and observations.
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Tenth (even) harmonic of a open-closed tube
Can I say that a frequency (let's say f1) is the "tenth harmonic" of an open-closed tube?
I would say it does not because closed tubes only have odd harmonics, is that correct??I want to ...
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What's the two-dimentional lock-in technique for STM topograph?
I have STM topograph data. I want to use the Lawler-Fujita algorithm to correct its drift, so I need its phase. I learned that the 2D lock-in technique can be used to acquire the phase of $T(r)$, but ...
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Difficulty Achieving Stable Alternate Phase Synchronization (APS) in Metronome Synchronization Experiment
I am doing an experiment regarding the synchronization of two metronomes. My setup consists of two metronomes and a platform and cans. I place the platform on top of the cans and the metronomes on top ...
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Evidence for the size of the nucleus [duplicate]
As a non-physicist, I find it hard to believe that the nucleus of the atom truly is so much smaller than the atom as a whole. What other evidence is there, apart from the gold foil experiment, to ...
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Question about conservation of total angular momentum in pion decay
I've been reading on conservation laws in particle decays, specifically total angular momentum. I stumbled on two other questions about the decay of a pion to two photons and why it's allowed. In one, ...
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What does the Fizeau experiment now do?
In 1848 Fizeau measured the speed of light by seeing how long it took to go a certain distance and come back. This fact is an excellent pedagogical tool to get people thinking that physical facts are ...
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Questions about the Stern-Gerlach Experiment Implementation
I have watched this video many times in the hopes of better understanding the SGE and how it is used to conclude that Quantum Spin must be quantized. I have two questions:
During the experiment, 9:40,...
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What experiments have been done which demonstrate that immediately after measurement, the collapsed state evolves unitarily again?
I am a high school teacher and in the coming year, I will introduce quantum mechanics to my AP physics course (I'm not actually in the US school system, but high school and AP physics are the closest ...
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Continuous Beam-Beam Collider Luminosity Calculation
I'm trying to do a calculation of a continuous beam-beam collider luminosity where the crossing occurs in a defined volume and the beams are defined by their current densities. But I am getting stuck ...
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What might cause excess counts in the first few bins of the histogram of muon decay times?
I did a measurement of atmospheric muons lifetime using a plastic scintillator, connected to a PMT with adjutable High voltage, a discriminator with a thershold voltage and an FPGA timer.
I was told ...
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How is quantum entanglement detected experimentally?
What type of detector was used to detect entanglement of different systems, for example, photons?
Are there new detectors being made now?
What technique is used for this detection?
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How can the air be warmer than both the floor and the glass ceiling of an aluminum foil-lined box in the sun?
I've constructed a styrofoam box, with the insides spray-painted black, on top of which I placed five layers of borosilicate glasses, air-gapped with a bit of cork. It is diagrammed below:
The box ...
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Rectangle-like structures and their folding in physics
It is well known that mathematics helps to explain some science problems. For example gömböc, which was a well hidden body from mathematicians, explains the body structure of some tortoises in ...
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Does a single-photon spread while propagating?
Assume a single-photon propagates along z in a glass fiber that terminates, creating an interface glass-vacuum. After a certain length in vacuum we have a photon detector array that gives the (x,y) ...
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Question: optical vector analyzer principle
i have a question about optical vector analyzer
i'm wondering about how to get the phase response of optical passive component.
In [Advances in swept-wavelength interferometry for precision ...
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Periodic fluctuations in photodiode signal, possible laser problem
Background:
I have a MaiTai BB Ti:sapph pulsed laser that I use for pump-probe transient reflectivity experiments. The output of the laser is split into pump and probe beams. The pump beam goes ...
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Procedure for Tauc plot from opaque sample
I would like to estimate the bandgap of a material and I would like to know if there is anything wrong with the following process,
I will estimate band gap from a Tauc plot. For the Tauc plot I would ...
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Can we measure $c=1$?
Usually the speed of light is measured using the S.I. units, yielding a result in $m/s$.
In geometric/Planck/Natural units it is known that we take $c=1$.
Clearly this is just a redefinition of the ...
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Analyzing the sensititivity of the estimate of a parameter to noise with Monte Carlo simulation
I am working with a perspective camera. I have the following equation for projection:
$$
v = \frac{f*y}{z-z_c}
$$
Here v is the coordinate in the image plane: $v \in [-1,1]$,
f is the focal length, y ...
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Bekenstein experiment to reveal the quantum foam
Bekenstein proposed an experiment to experimentally verify the Planck-scale space-time quantization. However, this has not been verified by subsequent actual experiments. What is it that cannot be ...
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What are the proper steps for taking a reflectance / tranmission spectrum of a solid sample?
When I began taking spectra of samples, I was lucky to have a spectrometer that basically did everything for me and produced spectra of samples that I would expect from literature.
I am now using an &...
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Are there any experiments that examine Hamilton's Principle directly?
Or can it be examined?
I 'd glad if you can share some ideas about "principles" in general.
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Calculating Bandgap of material from specular reflectance vs diffuse reflectance
I am looking for some clarification on whether specular reflection data can be used to calculate the bandgap of a material. I am using a UV-vis spectrometer and measuring the reflectance from an ...
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Continued calibration of atomic clocks
First off I am not well versed in physics, but as I understand things the second is defined by the ceasium fountain clock which is calibrated as follows How was the first atomic clock calibrated?. Now ...
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Will a Modified Maxwellian Demon Experiment Using Charged Particles Be Able to Recycle Heat?
(If necessary this experiment can be conducted in an environment where gravity is negligible to avoid gravitational effects.)
Two adjacent containers are filled with a homogenous gas composed of ...
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When building a fiber optic interferometer what methods are used to reduce microphonic effects?
When building a fiber optic interferometer what methods are used to reduce microphonic effects? I'm familiar with a few methods such as: enclosing the interferometer under a sound dampening cover, ...
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Why are laser beams not affected by gravitational waves in Michelson interferometer? [duplicate]
Michelson interferometers are used to detect gravitational waves. This means two laser beams are sent in long arms and reflected at the end. Usually, they annihilate each other and no signal is ...
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Are there any commercially made optical fibers which are made specifically to have very low microphonic properties for application in interferometry
Are there any commercially made optical fibers which are made specifically to have very low microphonic properties for applications in interferometry. While building a fiber optic interferometer I ...
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Can we tune chemical potential by electrostatic gating in solids?
I often hear that chemical potential in solids can be controlled by electrostatically gating the sample besides other methods such as chemically doping the sample. What are the limitations of ...
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Is it possible to find a function that approximately describes data points in series?
With a pH sensor we measured the output voltage in dependence of temperature. By measuring over a temperature range we obtained a data series. That way we created several series by using different ...
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Understanding Pressure Transmission and Lift Mechanics in a Hydraulic Lift
I'm trying to grasp the principles behind the operation of a hydraulic lift, particularly how pressure changes are transmitted and how they result in lifting actions. I have two specific doubts:
...
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Human error in wave experiment
I am trying to see what the fundamental frequency of a string is by slowly increasing the frequency on a function generator.
This experiment relies on the experimenter to record the frequency as soon ...
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Why laser output power fluctuates after passing through two 1x2 fiber optic couplers?
When laser source is launched into two 1x2 50/50 fiber optic couplers connected as below the output power constantly fluctuates in range of 70 uW.
The fluctuation happen roughly one to two times per ...
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Electron microscopy and Interatomic distances of miller planes
I am studying Transmission Electron Microscopy (TEM), and have been seeing in articles TEM images of different materials typically come accompanied by these diffraction patterns, caused by the ...
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Fitting function to compton continuum of data measured by scintillator detector
I have measured the spectrum of $ \:^{60}$Co with an NaI-scintillator detector. Now I want to fit a function to the measured compton continuum. My idea was, that the measured counts are proportional ...
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Why does detector inefficiency (or dark counts) count as a "loop-hole" in Bell-inequality tests?
Conceptually, I don't see why there is a problem with nonunity dection inefficiency or dark counts in a bell-inequality-measuring experiment.
Intuitively, isn't the point of the Bell-inequality to ...
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Where to find the Expectation Values of Aspect's and Clauser Experiments [duplicate]
Alain Aspect and John Clauser won the Nobel Prize in Physics for their epxeriments on quantum entanglement. Does anyone know where to find the raw data or at least published calculated expectation ...
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Second Harmonic Generation on chiral surfaces
I try to recreate a fit in this paper on SHG on chiral surfaces.
I guess the question itself is too specific to get an answer, so I state these questions that are a bit more to the point (and leave my ...
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Avoiding secondary flow in rotating fluid
I am required to create an annular flume for an experiment. The flume is to be filled with water, and a paddle is to be dipped into the water and rotated along the flume at some fixed angular velocity ...
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How did J. J. Thomson conclude that the particles present in cathode rays were not ions but are in fact much smaller than the smallest of all atoms?
What evidence did he have to prove that the particles in cathode rays are much smaller than atoms? Did he have the e/m ratio of hydrogen ion in 1897? If yes, where did he get that from?
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Quantum experiments at different heights from Earth
Suppose one were to perform the same quantum mechanical experiment - say the double slit experiment or any other quantum mechanical experiment with identical conditions, set ups and elements - while ...
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Arbitrary first and second moment for squeezed spin coherent state
Consider a spin coherent state of $N$ spin-$1/2$ atoms polarized in the $+x$-direction, denoted $\lvert \frac{\pi}{2},0 \rangle$. Now, squeeze this state in the $+z$-direction with a one-axis twisting ...
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How to be sure that when a muon passes a detector it is actually a muon?
The question is as follows: when you have any kind of detector for muons you just take measurements and you say, for example, the number for the muon flux but how you're sure that all particles ...
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Which experiments can offer insights about Hubbard $U$ parameter?
When considering $\mathrm{DFT}+U$ calculations, people either go with (1) first-principles approach: calculating the $U$ parameter using linear response theory, $\mathrm{DFPT}$, $\mathrm{ACBN0}$, etc.,...
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What is the solar radiative power on a clear sky day through a surface which is parallel to the sun's incidence on Earth?
Assuming that the solar power through the incident surface is known. How can we calculate or estimate the radiation through the parallel surface assuming a clear sky?
Looking for watts per square ...
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Experiment to determine friction coefficient
I've come up with an experiment to determine the dynamic friction coefficient of two bodies made up of arbitrary materials, and I'd like to know whether it is good enough or if it needs polishing (...
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Photoelectric effect - continuation of previous question (surface power density, diameter of photons, making converge 2 photons to same electron, etc)
This question is the continuation of a previous SE post of mine. Since I have $4$ questions to object to KDP answer, I decided to write this new post.
To sum things up briefly: we were concerned ...
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Disagreement between theoretical and experimental inductance of a coil
I have a coil of 20 AWG enameled copper magnet wire with approximately 270 turns: 9 layers of 30 turns. The coil is tightly packed with an overall height of about 30 mm, an overall outer diameter of ...
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Does the number of photoelectrons depend on the area of the beam for a given beam power?
I don't understand something in the photoelectric effect experiment (which consists in shining light to a metallic material and then measuring the kinetic energy of the ejected electrons, as well as ...
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What is the science behind why when displacement is increased, so will the final velocity? [closed]
I'm writing a paper and need to write a hypothesis. I did an experiment using a weighted cart with a string and falling mass, and also a pulley. This was completed on a flat table onto the floor. In ...
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