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Apr
16
comment Symbol $p^{0}$ of particle
I'm a bit confused because you both asked for a particle and tagged the question with particle physics, but accepted an answer about something quite different. Did you actually meant the zeroth component of momentum $p^0$ which is the conventional meaning of the symbol you supplied and the answer given below, or did you mean $\rho^0$ the symbol for a particular uncharged, vector meson which is the particle whose symbol most closely resembles the one you supplied and is often misidentified as a roman p?
Apr
15
comment Why only light nuclei are able to undergo nuclear fusion not heavy nuclei?
Related (in effect duplicates): physics.stackexchange.com/q/80256 physics.stackexchange.com/q/215769 plus physics.stackexchange.com/q/168237 and several others where the meaning of binding energy is explored in some detail.
Apr
13
comment How did we realize that light travels at a finite speed?
And there were already quite reasonable purely terrestrial measurements by the beginning of the 20th century.
Apr
13
comment Antique X-Ray Tube Safety
The dosimetry is the really stinker and the reason a E&HS rep would look askance at using this thing for a classroom demo. If you really want to run it for the cool factor, take video of yourself demonstrating it, then show the video. Our new display case is going to have a video-display on the opposite wall, so if we run our we'll put the video in the loop the screen shows. The place these things hold in the history of physics is important and worth explaining, but is it worth a unmetered (if probably small) dose delivered to a lot of students?
Apr
13
comment Antique X-Ray Tube Safety
We found something similar here, while cleaning out the prep room for a move to temporary quarters. It is destined for the display case when the re-model of our space done. You could operate it behind a bunch of shielding, but what would you gain by doing so?
Apr
13
comment Why do we use Bequerel to measure Radioactivity in food?
I used to approximate the activity of a banana as part of party trick we did for people visiting a place I worked at that had a low background Ge-detector system. But "decays" isn't a good measure of health effects.
Apr
11
comment What is the desest material on earth?
It always amuses me that people use lead as an exemplar for density when it is only middling dense compared to gold, mercury, and tungsten much less exotics like uranium metal, osmium, and heavymet.
Apr
11
comment Can special relativity be derived from the invariance of the interval?
@David Getting the general invariance of the interval takes some work, but the invariance of light-like intervals is the invariance of $c$. Like this: $c = (\Delta x)/(\Delta t)$ so $c \Delta t = \Delta x$ so $(c\Delta t)^2 = (\Delta x)^2$ so $(c\Delta t)^2 - (\Delta x)^2 = 0$. All those games Einstein plays with light clocks and so on rely on the invariance of light-like intervals.
Apr
10
comment Dalton's law of additive pressures
We have the MathJax math rendering engine active on the site, and it is preferred to posting images of math because it is editable and agrees in size and typeface with the rest of the post. I've done this one for you. You can fine some basic help on our formating page, and much more on on various latex site (MathJax's input language is approximate the same as LaTeX mathmode).
Apr
10
revised Dalton's law of additive pressures
remove image of math in favor of MathJax
Apr
9
comment Why must the plane of polarization be the same for two waves to interfere?
This is all correct, but not being able to get compete cancellation doesn't mean that you don't have interference: it means that you have a limited range of interference contrast dropping to zero contrast when the source have perpendicular polarization.
Apr
9
comment Why must the plane of polarization be the same for two waves to interfere?
Er ... you can get partial interference for incident sources which have difference in polarization that is neither $0$ now $\pi/2$.
Apr
9
comment Methods for handling close approaches in $N$-body simulations
Almost certainly already answered on Computational Science, which is generally a better site for questions that mostly concern programming technique.
Apr
9
comment Can special relativity be derived from the invariance of the interval?
Most of Einstein's methods are based on the invariance of light-like intervals, no?
Apr
9
revised Are wave fronts in double-slit experiments moving forward?
blue pencil stuff
Apr
9
comment Intensity of interfering light waves
You might find that the (many!) questions about energy and interference provide a different way to conceptualize this.
Apr
8
comment How do I make a slowly rotating neutron star using fortran code?
There is also Computational Science.
Apr
7
revised Spectroscopy, interferometry and …?
added 617 characters in body
Apr
7
comment Spectroscopy, interferometry and …?
And here I thought I was being slick.
Apr
7
answered Spectroscopy, interferometry and …?