Questions tagged [error-analysis]
Techniques and methods for computing, estimating, or placing bounds on the errors of expressions (formulas) based on knowledge of error distributions, error intervals or bounds of variables and parameters entering those expressions, and of methods used in the computations.
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Why use the QR factorization method to diagonalize a matrix? Considering better alternatives
Last year, I took a course in Computational Physics, where I learnt methods to integrate and differentiate functions, diagonalize matrices, etc. More precisely, I recall we would diagonalize matrices ...
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Has friction vs. altitude been measured at the same precision as atomic clocks?
Quick question for experimental physicists:
I'm preparing a proposal to test whether mechanical friction scales with gravitational potential exactly like atomic clock rates do. Before I submit it, I ...
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How to determine a fitting function from only an emission spectrum when using a different data set to isolate a specific dopant?
Imagine using a persistent luminescence crystal. Strontium aluminate, doped with Dy3+ and Eu2+. When exciting with UV light and X-rays it results in a different emission spectrum. Europium electrons ...
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Looking for an old physics lab meme (early 2000s)
I’m trying to track down a mock physics lab report / figure that circulated online in the early 2000s. It showed very noisy, essentially meaningless data, a clean straight-line (or simple) fit drawn ...
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Uncertainty for a Cooper Run
What is the correct way to report uncertainty for a 12 minute Cooper run?
This concerns IB-level student practical work, not degree-level experiments.
A 12-minute Cooper run is performed around a set ...
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Confused with Vernier Calipers [closed]
I've been lied to about the correct method to read vernier calipers by my teacher. And I realised it 10 years later when I myself become a teacher!
Sorry, for the rant, but I have to make sure, which ...
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How should you handle uncertainties of when determining mean count rates of radioactive sources?
When taking count rate measurements, I get a mean of 572.41 #/s. I have taken one measurement per second, totalling 596 measurements. After consulting Glenn F. Knoll's Radiation Detection & ...
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Is there any general principle for why small deviations in models give only small errors in predictions?
I have a question regarding the pragmatic heuristic that goes something along the lines of
"Small deviations from reality in a model yield small errors in the predictions of the model"
Is ...
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Scientific notation with/vs. complete integers
I got into a fight on the zsh forum over the fact that zsh uses '5.' to indicate the integer 5 but stored as a floating point number. I protested that '5.0' would be better since the trailing dot is ...
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What are the main sources of systematic uncertainty in $Δα/α$ measurements from quasar absorption lines?
Studies like Webb et al. (2011) and King et al. (2012) have reported small deviations in the fine-structure constant, α, using quasar absorption spectra at high redshifts. These rely on precise ...
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How can I determine the error for assuming earth is and using Cartesian coordinate system
While I was reading through HRK came across this problem
at the last picture it's asking
"Can you estimate the distance d that the airplane must fly before the use of flat Cartesian coordinates ...
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Does this spring work with Hooke's law or not? [closed]
In the table is the data from the spring. In the y axis is the force in Newtons, and in the x axis is the extension in meters.
Edit: I found out the reason why this spring did not work as initially ...
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Statistics for Theoreticians
I'm a theoretician, and as the years pass, I notice my knowledge of statistics and my memories of experimental physics classes fading and becoming more and more uncertain. Thus, I'd like to ask for ...
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Is it okay if your signal and noise have the same statistical distribution?
Please bear with me if this seems like a very basic question. Let's say you want to detect a signal by measuring a variable $x\in[0,\infty)$. Let's say you know the variable $x$ follows a probability ...
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Questions about calculations of significant figures
Essential Physics 4/e by Richard Wolfson states this:
In addition and subtraction, the answer should have the same number of digits to the right of the decimal point as the term in the sum or ...
