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4h
comment How do they know their velocity in a spaceship?
As things stand this remains primarily a pointer to off-site resources, with little of the answer summarized locally.
5h
comment Explanation of graphs from CERN
The upper plot here says what the dependant axis is in words. That makes its interpretation fairly easy. The lower one uses symbols which makes the interpretation much more context dependent, which is where @innisfree's comment comes in: you need to extract some information from the source of the plot to be sure you have the right understanding of those symbols. It's also worth noting the different scaling of the dependent axis: the top plot is semi-log while the lower one is linear.
14h
comment The energy of de-excitation
Watch out for the word "produced" here. Energy is transferred from one place to another and transformed from one one kind to another, but it doesn't pop into existence from nowhere.
14h
answered The energy of de-excitation
15h
comment How do you calculate the expected force of an electromagnet?
@don_Gunner94 You don't? I mean, you can wave your hands at it, but frankly the most that will accomplish is giving them a false sense of comprehension. The subject simply requires a certain level of knowledge to encompass.
15h
comment Trouble understanding a formula in Turbulence
Please copy the text (and mark it up as a quote, of course) rather than posting images of it. This makes a difference in several ways: (a) it makes the text searchable, (b) it makes the text available to users who use screen readers, and (c) it makes a fine-grained edit history available (though that is unlikely to be a major concern in this case). You'll want to use MathJax for the math, of course.
15h
comment Variation of Veritasium bullet block experiment
Note that an elastic collision certainly implies a different momentum transfer. Not just different from the fully inelastic case, but also different between the two cases that you propose. Finally, while I haven't seen the video that you mention without even bothering to link to it is likely that the situation you're talking about is properly called a "ballistic pendulum", and has been a common teaching scenario since long before the internet much less veritasium.
18h
comment How do you calculate the expected force of an electromagnet?
It you look in the "Related" sidebar you'll see many related (or duplicate) questions including Pull Force of an electromagnet. This is a very popular question, but it is also one that does not yield a tidy formula or equation. Sorry, but that's the long and short of it.
1d
comment Are all heaters exactly as energy efficient as each other?
Not that "heat produced" and "makes me warmer" are not the same thing. One is some kind of measure of the output of the device, the other of a change in your thermal balance. The latter depends on what parts of the space are getting heated, how fast the heat is dissipating, how quickly the air around your body might be moving and so on. So your question about adding a fan introduces factors other than the one you've attempted to focus the question on.
1d
comment Formation of nucleus
Required reading: physics.stackexchange.com/questions/3436/… and also physics.stackexchange.com/questions/133376/…
1d
revised Formation of nucleus
deleted 125 characters in body
1d
comment What determines the color of photon that is emitted from an exited atom?
"The color of the photon is related to its frequency $f$", is reasonable true, but only because you restrict it to light of a single frequency by considering only one photon. Light including contributions of multiple frequencies does not follow so simply a understanding because "color" is a sensory result rather than a physical property of the light and the processing your brain does on visual input is considerable.
Apr
28
comment Michleson Interferometer fringe shift
We have MathJax active on the site allowing you to write mathematical symbols and expressions in a LaTeX-math-mode equivalent language. I've done the Greek letters here for you. See physics.stackexchange.com/editing-help for a little help and the wide internet for more general help on LaTeX.
Apr
28
revised Michleson Interferometer fringe shift
latexify the symbols
Apr
28
comment How to motivate the importance of the spacetime interval
Because we're teaching the relativity unit of modern physics out of Tacheuchi, I've been using a geometric motivations, but I think it still needs refining. Moreover it really requires the decision to go with a geometric description of the physics from the beginning.
Apr
28
comment heat as a low quality energy
One of the many variation of the 2nd Law says that a refrigerator can't be perfectly efficient any more than a heat engine can. It costs you energy to make a colder reservoir than you have naturally available, making the combination of refrigerator+heat engine less efficient than just building a heat engine to take advantage of the available reservoir.
Apr
28
comment heat as a low quality energy
Note the distinction between 'net heat' and 'heat offered to the system'.
Apr
28
comment Is potential energy included in internal energy?
How did you classify bond energy, then? My guess is this misconception rises from overgeneralizing the case of the ideal gas as presented when talking about kinetic theory.
Apr
28
comment What processes create or destroy information?
Required reading: Liouville's theorem.
Apr
27
comment machine learning feature vector for periodic point distributions in 3D
I'm voting to close this question as off-topic because it is about machine learning and has nothing that makes it require the input of a physicist.