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Mar
17
comment Why do NMR spectrums have the higher chem shift values closer to x-axis?
Now asked and answered on Chemistry.
Mar
16
comment What is the exact value of the constant in the similarity solution for blast waves?
Can you explain which Rankine-Hugoniot equation and which similarity solution you used?
Mar
16
comment Focus correcting screen
I apologize for the close message -- this is definitely not engineering. It is however a duplicate of the above linked question. Unfortunately the system just goes with what a majority said (in this case, "engineering") and pretends everyone was unanimous in that.
Mar
16
comment Focus correcting screen
Possible duplicate of Is it possible to blur an image in such way that a person with sight problems could see it sharp?
Mar
15
comment Note and homework organization
Hi Jesse. While it's good that you are looking for the best ways to learn, we only answer actual physics questions here, not questions about how to go about doing physics. Also, whatever style of notetaking works for you in physics will apply in other subjects and vice versa.
Mar
14
comment How lens for specs are manufactured for a given power? Do thickness, refractive index play role?
Something to think about: what if the lens had the exact same index of refraction as air?
Mar
14
comment Why doesnt magnetic and electric field lines collide?
For close voters: the second sentence here clearly shows this is not asking about electric field lines crossing with themselves.
Mar
13
comment How do we measure Schwarzschild coordinates?
@Timaeus Nor is there a local way to measure the size of the Earth in Newtonian mechanics. At some level you either need to travel to elsewhere in space(time), or have a model for how to interpret information coming from elsewhere (e.g. the light of distant stars). This has been true in physics since long before Newton.
Mar
13
comment How do we measure Schwarzschild coordinates?
@CuriousOne It's no more or less meaningful than describing how to measure one's latitude and longitude. Yes, one can sail around the world without lat/long, but that doesn't make them worthless or ill-defined concepts.
Mar
12
comment Breaking the bottom board… when there's two
Sort of vaguely related: physics.stackexchange.com/q/71661
Mar
10
comment How does the propagation of gravity work for photons?
Who said you can feel the gravitational pull of a photon coming at you before you can see it? You can't! Also, necessary reading: Do two beams of light attract each other in general theory of relativity?
Mar
10
comment Where can I find data for the masses/component velocities of galaxies in the Local Group?
Also, you already have one velocity component from redshift. The other two, however, are not nearly as easy to ascertain as you might think. The transverse motion of even the nearest galaxy was only measured a few years ago, and it took one of the best telescopes ever built, together with years of patience, to do that.
Mar
10
comment Where can I find data for the masses/component velocities of galaxies in the Local Group?
Cross-posted to astronomy. Please just post to one site or the other.
Mar
7
comment How do snails avoid being cut while crawling over a razor blade?
While physics might be able to answer how a particular mechanism works, it is purely the realm of biology to say which mechanisms are employed by living organisms to achieve their ends.
Mar
6
comment Would a non-rotating Earth collapse on the Sun?
Fun fact: Venus essentially doesn't rotate about its axis. Hasn't fallen into the Sun yet ;)
Mar
5
comment What's so confusing about quantum physics?
Don't worry, QM isn't actually as confusing as most professors and science popularizers make it out to be, and indeed there is no physics whatsoever behind quantum interpretations. It sounds like you are in a good situation philosophically.
Mar
4
comment Is Moon too hot?
@CuriousOne ...which solves the issue and constitutes an answer.
Mar
2
comment Stability of plants and buildings: the role of the xylem
While a structural engineer might also have some insight, I feel this has enough physics to be on topic for us. The closure criterion is "does this question not fit here?" not "does this question fit better elsewhere?"
Mar
2
comment Finding the appropriate coordinate transformation given two metrics
This answer is very appropriate for this question.
Mar
1
comment Why is the detection of gravitational waves so significant?
@mpv While the surface of a pulsar is mildly strong-field, as a system of two orbiting masses even the double pulsar is very weakly relativistic. The orbital separation is $10^5$ or so Schwarzschild radii, and the orbital velocity is a fraction of a percent the speed of light. This may be $100$ times stronger than the relativistic effect on Mercury's precession, but it is still small. Note the theoretical predictions (which match observations) behind the Hulse-Taylor binary were done in the 70s, a good three decades before we could do strong-field numerical relativity.