Effects Definition and 963 Threads

It is becoming apparent that the COVID pandemic may be casusing more harm than originally thought. Months after recovering from noncritical infections from COVID people are developing medical conditions that are greatly affecting their lives. Symptoms include tremors, vertigo, double vision...

Hello all, I am struggling to find out what exactly makes to have very little advantage in terms of cold stopping distance when you fit larger brakes on a car. Important note, the discussion is only regarding the braking power in the very first stop, before the heat starts to become a problem...

One more thing i forgot to add, is magnetic permeability of a metal constant irrespective of its temperature including superconducting temperature ?

Hi all, I am trying to get it straight in my head how the interactions would work with a person (or accelerometer, for simplicity) suspended in a fluid, which is itself in a capsule which is then accelerated. Let's say with a rocket, on a linear track, to avoid any circular motion dynamics...

Hi. I don't know what prefix this question belongs in so I just chose advanced at random. What's the physical effect called when the Earth orbits around the sun at extremely fast speeds and also rotates around itself every 24 hours at the same time? Does that force cause anything in space...

I have two separate inquiries that may seem unrelated at first, but aren't. Firstly, I'd like to propose a thought experiment. Say someone studying Venus suddenly discovered incontrovertible proof of a biosphere on the surface, and a vibrant one at that. Eventually, Venus will disappear in...

If you want to critique this meta-analysis of case studies, please read the article. First. PLOS is open access. Anyone can see it. Note the ability to see the peer review process, which is interesting. "Occurrence and transmission potential of asymptomatic and presymptomatic SARS-CoV-2...

Suppose the Martian sends a signal to Earth, the final flash of which is emitted exactly four minutes later than the initial flash. In that case, with a favorable position of the planets, the final flash on Earth will also be observed neatly 4 minutes later (and 4 light minutes further than at...

What is the population density of ##H^-## hydrogen anions in the Sun's atmosphere, how stable are they, what limits their numbers, and since they are the dominant source of opacity in radiative transfer in stellar atmospheres, what do they effectively "hide"?

I'm a recently graduated MS in EE, I'm considering continuing onto a PhD. I'm wondering, what impact would starting a PhD and dropping out have on my career? Basically I'm considering giving it an honest shot for ~1 year and if I hate the experience leave. One year isn't a huge personal...

Hello everyone, I was doing some calculations recently regarding particle velocities for different elements at different temperatures and I have a few questions for the experts in here. Usual gas laws in my school book provides information about the velocity of particles in gases, it provides...

I have attempted solving this problem several times on an long since finished online quiz. However no answer I gave seemed to be correct despite what I could reasonably understand regarding the effect of seatbelts and their effect on reducing force by extending the distance of deceleration...

I am learning about hypersonic flow now and there seems to be a lot of discussion about the effects on oblique shock as the Mach tends to be very large. I was wondering what happens to the normal shock as the Mach number tends to be high and I can't seem to find anything about it. Is it because...

Summary:: The Hot chocolate effect is an investigation that extracts the essence about the effects on speed of sound. This is carried out in this sequence: A cup filled with liquid is continiously being tapped from the bottom. Meanwhile, a disturbance in the longitudinal sound waves is being...

Not another Corona thread surely?...yes but this time it's something positive we can take forward, when it's over. Several posters @Tom O [USER=283516]@davenn and others have made reference to reduced seismic activity due to lock down. That's great for Earth sciences and reduction in RTAs but...

Hello all: hope you are all well . as i am looking into reasons of death from Covid-19 i could see that pneumonia , is a major reason of death , but what kind of pneumonia ? i couldn't find on the internet is it only viral pneumonia or mix of types ? Best Hagop

Often heard that it's not good for health to work through the night and sleep in the day, is there any medical support on this issue?? Or only a belief??

I've read number of virus disaster novels, but I can't recall any of them predicting anything like what's actually going on now. Anybody know of novels where the author predicted details such as a moderately lethal virus - so not end of the world stuff - leading to lock down and governments...

Hello all: Reading about HB-11 start up and they mentioned laser induced magnetic field : How is that created and the size of the magnetic field is in kilo Tesla range anyone heard of that Best Hagop

Before today. I was thinking maybe cooking fumes didn't just get to your mouth but pass through your bloodstream, perhaps causing allergy. But when I googled it. I found many alarming articles about it. What is your comment...

Does the extreme gravity from a black hole cause a blueshift in light approaching the event horizon? sorry for the newb question

Hello all, Suppose that in a monopoly game (board game), a player passed through Go and receive $2000 as salary. Then he landed on Income Tax and he paid $2000 too. It means that he paid 100% tax rate, in other words he paid all of his salary only for the tax. What the effects and implications...

Hi everybody, Poisson's ratio determine that when applying force in one direction (let say z direction) it would cause a relative major strain at that direction, and also two additional strains at the two other directions (x & y). My question is, what is the explanation for the change in the...

Few days back, our college professor told us that if a photon were to have a finite mass, then the Coulomb potential between two stationary charges separated by a distance r would be strictly zero beyond some distance. He told us that it was due to the reason that photon is the elementary...

Summary: What if the Earth rotated about its axis in a N-S direction instead of doing so in an E-W direction. Hi, Just curious: What would be the effects/consequences if the Earth rotated about its axis in a North-South ( or South-North) direction instead of an East-West one as it currently...

That was my attempt , but I am not sure if my answer is correct or not . I want to confirm it .

There is the famous experiment of measuring the "movement" of a star close to the sun during an eclipse. The stars position is determined before the disc of the sun moves just under it and than the position is again measured when the sun moves just "under" the star. The star will have appeared...

Can the effects of gravity possibly extend through time? Is there a natural law that forbids this? Could this be a possible explanation for dark matter?

So, let's assume in a theoretical case we have a (semiconductor but not necessarily) device, e.g. a MOSFET, that is perfectly cooled and has zero heat resistance (infinite thermal conductivity), and that it's connected to a perfect heat sink (theoretical abstractions for now, I will come back to...

Shankar, in the book "Quantum Field Theory and Condensed Matter", at page 328 writes the famous bosonization formula in the form $$\psi_{\pm}(x)=\frac{1}{\sqrt{2\pi\alpha}} e^{\pm i \sqrt{4\pi} \phi_{\pm}(x)}$$ and then writes: "This is not an operator identity: no combination of boson operators...

The wavefunction is Ψ(x,t) ----> Ψ(λx,t) What are the effects on <T> (av Kinetic energy) and V (potential energy) in terms of λ? From ## \frac {h^2}{2m} \frac {\partial^2\psi(x,t)}{\partial x^2} + V(x,t)\psi(x,t)=E\psi(x,t) ## if we replace x by ## \lambda x ## then it becomes ## \frac...

Full disclosure: it's not tidal; I'm pretty sure it's a longitudinal harmonic wave - but I don't know the terminology. So today my bro and I went for a sail to Centre Island in Lake Ontario, as we often do. Lake Ontario is currently at its highest level in a long time - certainly in my...

Hi, is there any form of ginco biloba I can take that won't give me side effects like mabey biloba extract?

Hi all, Consider a platform with angular velocity ##\omega##. A particle on top of it has a velocity with only ##\hat \theta## component (no radial ##\hat r## velocity). In this case, the inertial forces read: $$ F_{in} = 2m\omega V_\theta \, \hat r + m \omega^2 r \, \hat r $$ If ##V_\theta =...

Summary: Gravity and ageing Hi I am new here, please may I ask, A celestial object creates gravitational pull, as the universe is expanding and accelerating, the spaces between objects unaffected by gravity, are they subject to ageing. A craft on a course towards an area would occupy those...

Summary: I was reading that the most powerful gamma ray burst experienced a 'drag' due to quantum turbulence and wondered how this could effect a plasma. After reading this Wikipedia article https://en.wikipedia.org/wiki/GRB_080916C I noticed the part about how the light was slowed down by the...

So there is no a full quantum theory of gravitation. However, there are instances where quantum effects due to gravitation have been studied. Like Gravitational neutron interferometry https://arxiv.org/pdf/1701.00259.pdf or maybe gravitational decoherence...

Summary: Does a static magnetic field affect a weaker pulsed magnetic field close by? If you have a static magnet close to a low level pulsed electromagnetic field, will the static magnetic field influence the pulsed field if the static magnetic field is the same strength or stronger than the...

A ballistics-esque question. Suppose we are driving at ##x \text{ m/s}## and we have to suddenly brake. For students in driving schools they are told something along the lines of "during the braking, the body experiences ##y \text{ kg}## of force" or "the mass of the body is much higher than at...

Summary: Relativistic effects on the quantum states of electrons in Copper and Gold Hello. I am a new member. I have read that the explanation for the colors of copper(red) and gold(yellow) compared to other metals being silver or grey in color is due to relativistic effects on the valence...

Friction is commonly thought to arise from the electromagnetic forces of the atoms at the boundary between two surfaces in contact. However it occurs to me that, in addition to charge quanta, there are also mass quanta present in this system and they could very well play a role. Now, I'm just...

I read that just a few feet difference in height would show a different rate of time and that was measurable. However, If the clock that is at a more elevated position it will be traveling through more space, is that what is responsible for the difference in the rate of time for that clock? I...

Hello, I'm Andrew and I'm in 12th grade. If you are interested, I would like to share a presentation showing the process, observations, results of an experiment showing the physical effects copper sulfate can have on early plant development. I, with much help from some intelligent members of...

Leitz Summicron 50 is one of the extremelly well corrected lens in the world. Legend says about this lenses internal elements and their spherical aberrations was responsible of lot of beatiful effects on image. For highly corrected lens image , does high internal aberration really effects the...

In https://en.wikipedia.org/wiki/Lamb_shift about the lamb shift, it's mentioned that the change in the electron's frequency due to QED effects (vacuum polarization and self-energy correction) is about 1 GHz, which would translate to an energy change of hf = 6.63E-25 J. This is 3E-7 times of the...

In QM. Can you use the Hamiltonian (or kinetic plus potential energy) to describe the forces of nature that should supposedly use QFT or Lagrangian? I mean the fields have kinetic and potential energy components and what are the limitations in description and others if you only use them to...

Quantum Electrodynamics (QED) has some observable effects such as the lamb shift, which is mainly caused by the vacuum polarization and the electron self-energy. These effects contribute to the "smearing" of the electron in an unpredictable manner, other than the uncertainty we already have...

Its been awhile since I even thought about conducting a scientific experiment, and I do remember that you need a dependent variable.. the observation or effect such as the apple fell from the tree, and then the independent variable, such as gravity. But in order to test the hypothesis, you...

When an airy disk is formed, does using a polarizer in front of the pinhole change the shape of the disk?

P. O’Hare et al. Multiradionuclide evidence for an extreme solar proton event around 2,610 B.P. https://www.pnas.org/content/early/2019/03/05/1815725116 https://www.sciencenews.org/article/one-strongest-known-solar-storms-blasted-earth-660-bc Extreme solar events, proton events, are not common...