filling in the unspecified details of elegant-sounding descriptions of experimental methods.

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5
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1answer
146 views

How does one align a laser using two adjustable mirrors?

Suppose we would like to get a laser beam to pass through a particular point in space in a particular direction. At our disposal we have a laser, two adjustable mirrors (can rotate up/down and ...
2
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1answer
140 views

Good algorithm for in-experiment 1-D optimization?

I'm running an experiment -- for the question, it doesn't matter which one, but I'm measuring an optical intensity $I$ as a function of two parameters: reflection angle $\theta$ and wavelength ...
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1answer
43 views

Uncertainty of approximately sinusoidal voltage measurement

Say one is interested in measuring the mean value an approximately sinusoidal voltage with an instrument that has an accuracy of 0.01 V, according to its spec sheet. 10 periods of the oscillation have ...
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1answer
18 views

How to experimentally identify the exposed face of a crystal?

After depositing a material (e.g, TiO2) on a substrate, what methods can I use to check whether the material is crystalline, and what face (e.g, 001, 101, etc..) of the crystal is exposed?
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508 views

Are the fast axes on Thorlabs quarter-waveplates mislabeled?

Some members of my lab are performing a polarization-sensitive experiment where they need to use a quarter-waveplate (QWP) with the fast axis in a specific direction. In the process of carefully ...
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0answers
205 views

Parity and Helicity of the Higgs Boson

I have been studying how the spin and parity of the new boson discovered at the LHC will be studied and have run into some confusion. The Standard Model Higgs is expected to be a scalar (i.e. have ...
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0answers
55 views

Alternative ways to take particle tracks photographs in a cloud chamber

I know that the most common type of particle tracks photography is in photographic plates, but i'm using a cloud chamber and I would like to know if there are alternative ways to take photographs of ...
3
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0answers
163 views

Production vs. Collection, and Contaminants vs. Depositions, what might be missing in cold fusion research

I though cold fusion and LENR were discredited, but just a few days ago I found out that NASA is claiming LENR is real. So I thought if they're detecting something, what could it be, and why wasn't it ...
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0answers
154 views

Obtaining point of application of Ground Reaction Force with use of a hyperstatic load-cell array platform

I'm looking for the theory of an experiment that is giving me a hard time to perform. I have an instrument composed of a rigid horizontal square plate rigidly supported under each corner by a ...
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0answers
30 views

Determining the spatial imaging resolution based on a pinhole diffraction pattern

I aimed a 780 nm/1mW laser at a 1μm pinhole and took a picture of it using a lens and a CCD camera. The magnification of my imaging system is ~25 times. I wrote some code that takes the image of the ...
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24 views

How is it possible to combine various techniques in cold atom experiments?

I’ve been reading about laser-trapped cold atoms (6Li in particular, which is a fermion) and was amazed at the number of things to keep track of in the experiments, just to gain that degree of control ...
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27 views

Can water seep in?

Today morning I was sweating a lot, and a drop of it directly fell on my iPhone's home button. Considering the height of fall to be approx. $30 cm$, I started wondering whether water could seep in. ...
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0answers
43 views

Kirchoff's voltage law doesn't seem to hold in an experiment conducted with series resistor, diode and signal generator

I've conducted an experiment to look at the electronic characteristics of a diode. This was done using a series diode, resistor ($R$) and signal generator. The signal generator was made to supply a ...
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0answers
178 views

Help understanding Fizeau's calculation of speed of light

While searching for different methods of calculating Speed of light, I came across one of the methods that Fizeau discussed below which I cannot fully understand. In short, in Fizeau’s apparatus, a ...
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0answers
33 views

Using GPS Satelites as dark matter detectors

Recently, two scientists have proposed a new way of detecting dark matter, using GPS Satellites. A part of the article is posted online: Hunting for topological dark matter with atomic clocks. Can ...
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0answers
46 views

What is the error on measuring the phase of a sine wave?

Let's say I have a wave, with frequency $\omega$ and phase $\phi$, of the form: $$y(t) = 1 + A \sin(\omega t+\phi)$$ where $A < 1$. I have measured this wave N times, and we can assume these ...
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15 views

Reverse polarity vs falling in Millikans experiment

There are multiple methods of hot to perform Millikans oil drop experiment. One of them lets the drop rise through an electric field (and measures the velocity) then lets if fall (without an electric ...
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0answers
43 views

High resistance wire as a heating element

I'm redesigning one of the labs for our senior lab class at my university. It's a thermal conductivity experiment meant to measure aluminum's thermal conductivity in a thin (1.1 cm diameter) rod. I ...
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0answers
48 views

Errorbars for data series with variable number of points and several layers of uncertainty

I'm making a 2D plot of my microwave S Parameter data and want to represent the error bars correctly. Experimental Context: I measure S21, (Vout/Vin), as a function of frequency and drive power with ...
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26 views

How big can be gradient of magnetic induction (in lab)

I'm thinking about magnetic levitation and how big force can push a diamagnetic when we put it in inhomogenious magnetic field. As far as I know, force exerted on a diamagnetic is proportionald to ...
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0answers
162 views

Measuring a quantity using two measuring devices

I would like to ask how I can reduce uncertainty by designing an experiment. I need to measure a quantity( say speed, in m/s). I have to calibrate the device and then move the device to measure ...