0
votes
0answers
8 views

What happens when two balls collide?

What happens when ball traveling at constant speed hit resting ball with same mass more mass less mass (ie. how diagram of balls speeds looks like) Balls are made of same material and they ...
0
votes
0answers
6 views

How to tell whether a wave is coherent or not?

I know that coherency means constant phase difference,but how to figure it from equation? Are all sinusoidal waves coherent?
0
votes
1answer
4 views

Quality factor of an LCR circuit

The quality factor of an LCR circuit is defined as: $$\omega°/2\delta\omega$$ $\omega°$ stands for the resonant frequency, and $\delta\omega$ for the range of frequencies between half power point and ...
0
votes
0answers
8 views

LIGO discovery: what in the paradigm hierarchy is that that is not wibbling?

Regarding the wonderful 2016 news about gravity waves. Something that confuses me is that: the gravity wave burst from the black hole event wibbled spacetime "itself". Again, my understanding of a ...
0
votes
0answers
18 views

what is the meaning of infinite mass?

IF a particle/object is moving at speed of light (v=c), using relativistic mass equation we get 0 in denominator i.e. m = infinite. So what is the meaning of that? At v= 0.99c as per the arithmetic ...
0
votes
0answers
3 views

Transformers: relation between their current, voltage and resistance

My current understanding Transformers are used to step up and down voltage keeping power constant. Hence, for example, if I step up some voltage, the current will decrease in the secondary circuit. ...
0
votes
2answers
10 views

Velocity selector and charge to mass ratio of an electron

I recently read that J.J. Thompson used a velocity selector to find the charge to mass ratio of an electron. Having learnt the principle behind the velocity selector, I see no relation between these ...
0
votes
0answers
7 views

induction of voltage from power lines to telephone lines

A pair of isolated parallel power lines of 1 cm radius with a separation of 90 cm have a voltage difference of 440 V. These power lines are 60 cm above a pair of telephone lines. The telephone lines ...
2
votes
2answers
53 views

Could discovered gravitational waves in fact be an aether wind?

Proving the existence of gravitational waves might revolutionise cosmology, but the method used by LIGO is quite similar to the famous Michelson-Morely interferometer built more than a hundred years ...
0
votes
1answer
8 views

Producing negative energy/exotic matter with particle accelerator for warp drive

Is it possible to make exotic matter or negative energy in particle accelerator for warp drive and for wormhole? If not what are the possibilities for creating negative energy.
0
votes
2answers
52 views

Could LIGO discovery be due to e.g. earthquakes or have a terrestrial source?

I mean, could it have been earthquakes or anything else?
0
votes
0answers
13 views

resource recommendation for understanding moment of inertia

I'm a student majoring in mathematics and have to study mechanics this semester .I had problem in understanding concept of moment of inertia. So is there some nice place from where I can understand ...
0
votes
0answers
9 views

How does wavelength affect scattering of light rays?

I am asking how wavelengths affect scattering(not diffraction). We know lesser the wavelength, greater is the scattering. For example, violet ray(wavelength 0.4 micron) is scattered most and red ...
1
vote
0answers
26 views

Does the speed of light change?

I know that there is a similar questions, but I think mine is a bit different. I wonder if with the expansion of the universe the speed of light changes. It seems that the speed of light is very ...
0
votes
1answer
9 views

Magnetic field lines opposite to actual direction

I was reading about purely inductive AC circuits. This is how the book tries to explain what happens in each cycle. As it can be seen, in the first and the fourth scenarios ,some magnetic field ...
0
votes
0answers
18 views

What happens to a a body if it rotates extremely fast?

I am thinking on a object, e.g. ball or planet that starts rotating with increasing speed. Let's assume that his speed get's closer to the speed of light, what happens to this object? There are ...
0
votes
1answer
23 views

How is water falling from a tap an example of the conservation of mass?

In a book, Conceptual Physics by Benjamin Corral, it was given that when water falls down from a tap, it is a case of conservation of mass. They said that this is because water is thick when just ...
-6
votes
0answers
13 views

How can I improve google ranking for my gaming site

http://feverofgames.com/ This is my site. I am facing difficulties to improve google ranking.
-1
votes
0answers
11 views

question on position in relation to source

Imagine a scenario where there is a source point and an emergent position of observation. The emergent position originates at the source. The distance between the source and the point of observation ...
-1
votes
0answers
35 views

Why quantum field theory is never used in engineering?

I love physics, but I really don't like engineering! Reasons: Physics has a lot more mathematical stuff; mathematical stuff is the most interesting Physics is a lot more general than engineering I ...
0
votes
0answers
20 views

How do gravitational waves and black holes interact?

Following the first detection of gravitational waves yesterday (11 Feb. 2016) by LIGO, I have a couple of questions about how gravitational waves and black holes interact. Assume that there is a ...
0
votes
0answers
7 views

parallel transport and absolute differential between 2 vectors

$\alpha$ I try to apprehend the notion of covariant derivative. In order to undertsand better, here is a figure on which we are searching for express the difference $$ \vec{V} = \vec{V}(M') - ...
0
votes
0answers
10 views

Calculate the laser heating on a crystal

Let's say I'm doing an optical experiment. I focus a laser on a crystal with a certain amount of power. The crystal's temperature is regulated to a certain temperature but it is localy heated by the ...
0
votes
0answers
8 views

Simulation of circulation on pavements between walkers and unicyclists

I am a fan of electric unicycle. I am interested in the interaction between electric unicycle and foot-walkers. The question here I would like to answer is: is it dangerous to mix on a pavement, ...
2
votes
1answer
40 views

What is time, does it flow, and if so what defines its direction?

This is an attempt to gather together the various questions about time that have been asked on this site and provide a single set of hopefully authoritative answers. Specifically we attempt to address ...
0
votes
0answers
24 views

Is it really just a gravitational wave that curves spacetime or is there also something else involved?

Gravitational waves are quadrupole waves which can stretch and sqeeuze space. So when a wave is passing through you you get taller and thinner and shorter and fatter. Like on a water wave you get up ...
0
votes
0answers
18 views

Basis for Derivation of Stokes Frictoin law for spheres

List item When deriving Stokes law one uses the Navier Stokes equation with the assumptions: 1) low Reynoldsnumber 2) stationary flow 3) in compressible flow leading to this version of the ...
0
votes
0answers
10 views

Hagedorn temperature as a control parameter of saddle - node bifurcation

Can we interpret the Hagedorn temperature as a control bifurcation of equilibrium parameter of the saddle - node type?
2
votes
0answers
25 views

Identical particles and topological phases

I've been wondering about the argument that is always put forward for why the only possible identical particles in three dimensions or more are bosons or fermions. My question is related to a very ...
0
votes
0answers
4 views

Hydro electric energy transformation

Suppose you have a water source of 2L/s at a given altitude. Suppose you carry that water down to a reservoir 200m below. At that point you settle a hydro electric water turbine to convert the energy ...
2
votes
0answers
44 views

Now that gravitational waves have been discovered, what does their particle version look like?

Duality dictates that gravitational waves should have a particle counterpart too, right? Will this in any way help solve the big problem of quantum gravity?
0
votes
0answers
29 views

Why does a curved spacetime result in a movement?

If gravity is not a force but a curvature of spacetime, where does the motion towards the center of gravity come from? To put it differently, why would two objects in a space fall towards each other ...
0
votes
0answers
29 views

Sakurai Exercise 2.17 (Harmonic Oscillator, Ladder operators)

I the field of the harmonic oscillator and ladder operators I am trying to solve exercise 2.17 from Sakurai and want to proof the following relation $$ \langle x^{2n} \rangle = (2n - 1)!! \langle ...
2
votes
1answer
28 views

Is it possible that there are still gravitational waves of the big bang?

We already discovered the cosmic background radiation what are the 'leftovers' of electromagnetic radiation of the big bang. Probably gravitational waves of the big bang (if they exists) would be to ...
0
votes
0answers
8 views

Superconductive contour

We have a superconductive contour in the shape of circle with radius $a$ . Inductance of contour is $L$, when the contour is out of magnetic field, there's no current in it. What's the current in the ...
0
votes
0answers
20 views

What happens to the radius of a sphere if I double the number of atoms contained in it?

I'll get a lot of downvotes eventually, but I've been trying to answer this questions for months. Scenario: Say I have a sphere containing helium. I've always wondered what would happen if I double ...
0
votes
0answers
6 views

Bondi mass aspect

I'm looking for a good reference that defines the Bondi mass aspect and his relations to Bondi and ADM mass. Googling a bit I've not founded any satisfactory exposition of the subject. A short ...
0
votes
0answers
8 views

Compton Scattering problem verification

A photon emergre in an angle $\theta=\frac{\pi}{4}$ in a Compton scattering the kinetic energy of the photon is $K_i=2K_f$. I must find $K_i$ in $MeV$. $\lambda_f -\lambda_i= \lambda_c$. Then: ...
0
votes
0answers
13 views

Wavefunction overlap in graphene

In calculation of the response functions of graphene we need to calculate the 4-point correlation function of the form : $$ \langle T \rho(q,\tau)\rho(-q,0)\rangle $$ The article I'm reading states ...
0
votes
4answers
49 views

If I push or hit an object in space will it rotate or move along a straight line?

If I push or hit an object in space (vacuum and no gravitation) in direction what is not going trough its centroid, will it rotate or move along in straight line? I expect that on earth it will ...
0
votes
1answer
28 views

Confusion in a problem

This is a very basic homework type question. I guess there is some intermixing of concepts in my head. Help. There was a question I came across - A ball of mass 0.2 kg is thrown vertically upwards ...
0
votes
1answer
26 views

Generating electricity

Why is it when we talk about generating electricity we only try predominately using only one type, eg. Solar, fossil.etc. Why do we not use them in series to ensure a greener generation of power? ...
0
votes
0answers
7 views

Intuitive picture for spin-fluctuations contribution to sign reversal of S+- state

In conventional superconductor, electron-phonon interactions lead to negative paring potential and further s-wave superconducting gap. One mechanism for superconductivity in iron-based ...
0
votes
2answers
24 views

Inductance coil with self-inductance and resistance

If a coil has $L$ henry self-inductance, resistance of $R$ ohms and potential deferens of $V$ volts what will be the current through it? In my opinion this case should be considered as resistance and ...
0
votes
1answer
28 views

General properties of Matsubara frequency summations

By properties, I mean linearity, shifting, commutativity, etc. I was hoping to evaluate something like $S_\eta = \dfrac{1}{\beta}\displaystyle\sum_{i\omega} g(i\omega)$ where $g(i\omega) = ...
0
votes
0answers
4 views

Grazing angle in a nuclear collision

How is the grazing angle calculated theoretically? Also, experimentally, the quarter point angle of elastic scattering angular distribution is taken as the grazing angle in accordance with ...
0
votes
1answer
15 views

Precise definition of “Observable Universe” and its alternatives

The Observable Universe is generally said to contain all space that could "in principle" have had a causal impact on Earth, but the exact limits of the "in principle" causal interaction go ...
0
votes
0answers
16 views

Number of impacts nitrogen molecules make with the palm of a hand

What is the number of impacts one mole air makes with the palm of your hand assuming air is entirely made up of nitrogen?
1
vote
0answers
23 views

What is the effect of gravitational waves on time? [duplicate]

I always struggle with the time concept when it comes to general relativity. In the recent discovery the gravitational waves have been detected by the "displacement" of the mirrors and the difference ...
1
vote
0answers
17 views

In GR what is a “source-frame mass”?

In the recent LIGO paper, they refer to the masses in some models as: "... a nearly equal mass black-hole binary system of source-frame masses $36^{+5}_{−4} M_{\odot}$ and $29^{+4}_{−4} M_{\odot}$ ...

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