In what respect (and range) is the model well tested?
Again, I'm not saying that the physical phenomenon does not take place. I do believe that humans are able to hear those faint noises.
Assuming that any model of a physical phenomenon has a range of validity, I'm wondering whether this...
Yes, I can see how pitch would be immaterial for primordial hearing. On the other hand many species signal via specific pitches. It could be useful to be able to hear the call of a potential mate from a very large distance.
Anyway my question was prompted by Steve4Physics' comment about...
All this is very interesting, but I still have some doubts about the result of the original problem. As I say, my doubts are not about the ability of human ear of hearing very faint sounds. I am wondering about the validity of the model at such a small scale.
I found that the typical...
I also thought of that. But in that case we are trying to measure a distortion in spacetime, and using laser interferometry.
I'd say that the underlying physical model (General Relativity) treats spacetime as a continuum, which makes sense since everything else is "inside" spacetime.
I guess...
Hmm no wait.
I might be mistaken, but the way I figure it is that a wavefront is a plane the same size as the eardrum. As the wave hits the surface of the eardrum each of the atoms in the first layer might very well be displaced by ##s_m##, or even ##2 s_m## considering a complete oscillation...
Hi,
I am not sure I follow.
Are you suggesting that ##s_m## is very small, but after all not so small if compared to the distance between two layers in the atomic structure of the eardrum? Like 0.1 angstrom vs more or less 1.5 angstrom?
Hi,
thanks for your answer. I am not questioning the sensitivity of human ear, though.
We can hear intensities from 1e-12 to 10, which is 13 orders of magnitude. I am not referring to the ability of distinguish between frequencies. Here we have one frequency.
The point is that the we have an...
The problem per se is pretty straightforward:
##s_m = \frac{\Delta p_m}{v \rho \omega} \approx 1.1\cdot 10^{-11} \, \textrm{m}##
I found an exercise similar to this in a translation of Cutnell and Johnson's "Physics" 9th edition. I could not find the problem in the original version of the book...
I tried to reproduce these curves. The values for the resistance are shown in the graph. The other values are ##L=100 {\rm \mu H}## and ##C=100 {\rm pF}##.
Using those values I get a much flatter curve, where the value at 0,9 is roughly 83% of the value at 1,00.
Am I missing something?
It seems...
Of course I understand that it must be so, in order for the solution to depend only on the translation speed of the tape. The contact times should not depend on the approach speed, in the FoR of the puncher.
However I cannot figure out an easy argument for this that does not involve knowing the...
it seems natural to assume that the amount of tilting (and hence the amount of delay) depends on the approach speed.
So, in the end, this effect should cancel out in some way, if only the horizontal velocity of the tape determines the area of the hole.
This is not obvious to me.
Now I'm starting to see it, also thanks to the diagrams.
So the cutting ring is horizontal in the FoR where the tape is moving (horizontally), but it is tilted (and not moving vertically) in the FoR at rest with the tape. One of its ends touches the tape before the other end.
This must have to...
I really do not understand. The tape is in a horizontal plane. The only way a cylinder can cut a round hole into it is when its axis is vertical, i.e. perpendicular to the plane.
The cylinder is above the tape, then it goes down through it and emerges below it. If the tape is not moving...
I'm not sure I'm understanding you correctly. Are you saying that the sides of the puncher (along the direction of motion of the tape) touch the tape simultaneously in the FoR of the puncher, but not simultaneously in the FoR of the tape?
Of course I do agree with the fact that two simultaneous...