instruction stringlengths 31 24.3k |
|---|
So I've learnt that the formula for optical path length is $OPL = ns$, where $n$ is refractive index of the medium and $s$ is its geometrical length, the problem is i cant really get around this formula like where does it come from? I tried deriving it but couldnt get anywhere.
I tried adjusting the last equation usin... |
I was following lecture notes of Sidney coleman (https://arxiv.org/abs/1110.5013)(page 7) where he stated:
"The addition of relativity is necessary at energies $E \geq m c^{2}$. At these energies
$$
p+p \rightarrow p+p+\pi^{0}
$$
is possible. At slightly higher energies
$$
p+p \rightarrow p+p+p+\bar{p}
$$
can occur. T... |
It is straightforward to show that
$$ \left[T_\leftarrow\exp\left(-i\int_0^tH(\tau)d\tau\right)\right]^{-1} = T_\rightarrow\exp\left(i\int_0^tH(\tau)d\tau\right), $$
where $T_\leftarrow$ and $T_\rightarrow$ impose time-ordering and anti-time-ordering, respectively.
I'm wondering what the inverse of
$$ \left[T_\leftarro... |
when given a particle of mass $m$ in a one dimensional square potential well from $x=0-L$, How can one calculate the value of the normalisation factor $|φ\rangle = |A|(\,|1\rangle + |2\rangle\,)$ where $|A|$ is the normalisation factor? Do I have to square the normalised wave-functions for the allowed value of energy?
|
According to Wikipedia:
Earth's rotation is slowing slightly with time; thus, a day was shorter in the past. This is due to the tidal effects the Moon has on Earth's rotation. Atomic clocks show that a modern-day is longer by about 1.7 milliseconds than a century ago, slowly increasing the rate at which UTC is adjuste... |
Update : found this video of The Sun can’t work without Quantum Tunneling that expands on the accepted answer, including it for completeness.
Fusion/Fission is always accompanied by the special relativity relationship of $E=mc^2$.
Yet there are atoms that are undergoing change, and that should be in the realm of Quantu... |
Can someone explain to me all about potential difference. It is basically taught when teaching about voltage but I want to know all about potential difference.
|
Why we can't make chain reaction in fusion or we can't use fusion products .
Deuterium $-$ Helium$-3 $ fusion :
$$2D + 3He → 4He + 1p + 18.3 \text {MeV}$$ (I found in Wikipedia)
If we can do the above reaction can we use this proton energy to make another reaction ?
|
Newton came up with gravity to explain apple falling from the tree, what would Gibbs have thought?
The second law states that entropy of the universe, in general increases. This is relatively easy to see when you expand a gas or dissolve salt in water but how is entropy increasing by the falling of the apple. Of course... |
$V$ is electric potential.
From my understanding of these notations
\begin{align}
V_{ab}&=V_a-V_b\\
\Delta V&=\Delta V_{ab}=V_b-V_a;\text{consider $a\to b$}\\
\Delta V_a&=V_a=V_a-V_\infty
\end{align}
Do I understand these correctly?
|
So when an iron particle is near a permanent magnet. We see that iron particles will be attracted to the magnet and the iron particle will experience a force directed towards the north or south; is it possible to calculate the acceleration and time taken to reach the magnet.
Is this force quantifiable?
I don't think a ... |
I think I can understand hall effect using the right hand rule, the electrons experience lorentz force in the presence of a magnetic field but I don't get why quantum? I saw the resistivity looks like a stepped graph why do electrons behave in such a manner like a current flowing through a multi stages zener diode? (O... |
I read here that the equation of resistive drag $F = -bv$ can be used, assuming the particle is moving
through a fluid at relatively slow speeds where there is no turbulence (i.e. low Reynolds number, $R_{e}<1$)
In order to decide whether I can use $F = -bv$, I need to identify the Reynold's number of the rigid objec... |
So if we look at the inhomogenous Helmholtz equation
\begin{equation}
\nabla^2 u+k^2u=-f
\end{equation}
and include the sommerfield boundary condition
\begin{equation}
\lim_{r \rightarrow \infty } r^\frac{n-1}{2}(\frac{\partial}{\partial r}-ik) u(rx)=0
\end{equation}
the solution should be
\begin{equation}
u(x)=(G*f)(x... |
A block of mass $2kg$ is kept at origin at $t=0$ and is having velocity $4{\sqrt 5}$ m/s in positive x-direction. The only force on it is a conservative and its potential energy is defined as $U=-x^3+6x^2+15$ (SI units). Its velocity when the force acting on it is minimum (after the time $t=0$) is
And the Solutions i... |
The standard way of describing neutrino oscillations seems to be that the mass eigenstates differ from the flavour eigenstates, which leads to an oscillation of neutrino flavour over time.
However, every other change in the Standard Model seems to be mediated by a gauge boson, so I was wondering why neutrino oscillatio... |
I do not know if this is the correct place to ask this but I do not know where else to ask. This paper https://doi.org/10.1016/0920-5632(90)90647-D has 15 references at the end. However, in the text there are citations to articles that are not referenced. For example at the end of page 66 there is the citation [26, 27,... |
The scenario I am putting forward is something like this:
Can the string really be perfectly straight and horizontal as shown in the picture(i.e can perfectly horizontal circular motion exist)or is it just an ideal situation?
Secondly what force is acting on the ball/stone which is balancing the weight of it in the dow... |
I read, that for normal diffusion the root mean square displacement $\sqrt{\langle x^2(t)\rangle}$ (for particles at the origin) can be interpreted as the mean distance the particles have with respect to the origin at time $t$. For normal diffusion, the MSD is $$\langle x^2\rangle=2Dt$$ and therefore the RMSD equals $$... |
Suppose that the electrons move with a speed of 0.0005 mm/sec in the copper wires. Do the electrons move with the same speed in the tungsten filament as well? This has to be true if current is same in both the wire and tungsten. But the resistance of tungsten is very high in comparison to copper, shouldn't the current ... |
On page 10 of this paper on quantum field theory. There is the integral:
$$\ln(N(T)) \propto \iiint\limits_{-\infty}^{\infty} \ln (\sinh(T \omega_k)) d^3k$$
where $\omega_k$ is the energy $\sqrt{|k|^2+m^2}$
Now cleary this integral is divergent. Is there any way to make sense of this integral to give function $N(T)$ th... |
I've been googling around and I can't find any direct explanation of why N2 TEA lasers are never shown to be used to demonstrate optical(dielectric?) breakdown or sparks in the air.
Would someone please help me understand what it is about N2 TEA lasers that make optical breakdown difficult/impossible?
I appreciate your... |
Searched this question a lot in different places but could not find any answer that could satisfy me. So I am here to clear my concepts regarding virtual displacement. Now I am clarifying my doubt.
As my textbook "A Student’s Guide to Lagrangians and Hamiltonians" by Hamill says on p.11:
A virtual displacement, $δx_i$... |
I am just curious to know whether Physicists have given any measurable Entropy to the Universe? If yes then please tell me whether its value is increasing or decreasing overall?
|
So you are holding a thin horizontal rod (which is not bendable) which is fairly heavy and there is a heavy object (lets say a bag full of heavy stuffs) hanging from it.
So now if the bag is shifted towards the end at which you are holding the rod, it seems that we are putting the same amount of force in the upward dir... |
I was a physics major a couple years ago and took a few undergrad and grad general relativity classes, got decently good at it, but changed majors and have forgotten most of the stuff. I wanted to delve into the subject again, but this time look more formally into the math and physics, if that makes sense. So I wanted ... |
Here is a question >
Two wires A and B of same material and mass have their lengths in the ratio $1:2$ .On connecting them to the same source , the rate of heat dissipation in B is $5W$ . What will the rate of heat dissipation in $A$ ?
My theory of doing it :
We know $R = \frac{\rho l}{a}$
Both wires will have diffe... |
There must be something really obvious that I am missing here but any help is appreciated.
Suppose I have a theory with some action $S$ on some fields $\phi$ such that any function vanishing on-shell has the form $\frac{\partial S}{\partial\phi^i}F^i$ for some $F^i$ functions of the fields. Assume that an irreducible c... |
Problem:
A uniformly charged circular arc with linear charge density $m$ subtends angle $\theta$, find the net force acting on a charge placed at its center if total charge of the arc is $Q$ and the charge at center is $q$.
Here, we take the line of symmetry for the arc and integrate the components of force acting al... |
Consider a hypothetical particle, a particle which is devoid of any kind of potential energy. Suppose the particle is currently at rest. Now what we are gonna do is apply a force on this particle. My question is such...
The force should be responsible for supplying velocity or rather kinetic energy to the particle thro... |
This circuit appears to clone bits.
The first picture is the copy circuit which takes |1000> to |1010>.
The second picture is the same copy circuit but it's copying hadamard states.
The third picture is copying a bell pair.
Since the final non-zero amplitude are all on the diagonal, and the phases are the same, the cir... |
I am trying to understand how to construct an action using the superspace formalism for $\mathcal N>1$. I have read that this is quite difficult to do, so let's consider a simple example. Suppose I want to construct an action for $d=1$, $\mathcal N=2$ supergravity with an $\mathcal O(\mathcal N=2)$ local symmetry. Such... |
In its article about Bell's theorem, wikipedia states here that the value of the correlation:
$$ C_q(a, b) = \left\langle A \left|(\boldsymbol\sigma \cdot \mathbf b)^{(2)}(\boldsymbol\sigma \cdot \mathbf a)^{(1)}\right| A \right\rangle $$
is
$$ C_q(a, b) = -\mathbf a \cdot \mathbf b $$
without any reference nor explana... |
I believe a magnetic field is caused by movement of charged particles.
But, what is it that is actually making the force between two magnets repel or attract to another? For repelling, I'm mentally visualizing a water balloon between two magnets. What is the water balloon composed of? Is it purely the "magnetic field"?... |
It is well-known, that in $\phi^4$ theory in 3d there is interaction fixed point:
$$
S_{\Lambda} = \int d^dx \left[\frac{1}{2}(\partial_i \phi)^2 + \frac{1}{2} \mu_0^2 \phi^2 + \Lambda^{d-4} \tilde{g}_0 \phi^4 \right]
$$
From equations of Wilsonian Renormalization group we immediatly obtain WF point, using $4-\epsil... |
I am currently studying the textbook Physics of Photonic Devices, 2nd edition, by Shun Lien Chuang. Chapter 1.3 The Field of Optoelectronics says the following when discussing quantum wells:
The effect of uniaxial stress perpendicular to the junction on the threshold current of $\text{GaAs}$ double-heterostructure las... |
I'm a mechanical engineer (this question might be very fundamental), and I am working on simulating the behavior of a particle in water when subjected to an electric field. In my simulation, I am using Maxwell Stress Tensor (MST) to calculate the electric stress and apply it as a volume force to the particle and water ... |
I have been very interested in this question since reading Electricity Misconceptions by K-6
There are two perspectives I have come across for how energy flows in a circuit:
Electrons carry charge. As the charges move, they create an electromagnetic field that carries the energy around the circuit. The electrons do no... |
The question is extention of thought experiment proposed by Einstein of light pulses in a train cart called Einstein's train. Assume that light pulses are emitted from the end of cart, instead from the center, such that stationary observer, sees the light pulses at the center crossing each other at the same time. imag... |
Background
I was looking into the definition of temperature and how it relates to entropy and internal energy and I came across this answer on StackExchange.
According to the answer:
[Temperature is] the differential relationship between internal energy and entropy:
\begin{align}
dU &= T\,dS + \cdots \\
\frac{\partial... |
When a thick plate of glass is hit (strong enough) by an object (say a shoe, by which I don't like to encourage vandalism, but I think that's happened when I saw the glass plate at a train station). This gave rise to the following structure of the plate (more or less; I didn't take a photo) and what I saw resembled the... |
Consider a 2d scalar field theory with quartic interaction
$$S[\phi]=\int d^2x \left((\nabla\phi)^2+m^2(\phi^2+g\phi^4)\right)$$
I want to compute the partition function
$$ Z[m,g]=\int\mathcal{D}\phi\,e^{-S[\phi]}$$
say as a function of $m,g$. I want to do this in $m^2\to\infty$ limit keeping $g$ finite.
Short statemen... |
I am trying to look for a stochastic resonance in a system described by Langevin equation and a periodic forcing. While I can simulate an SDE numerically I have no idea how to calculate the 'signal to noise
ratio' which quantifies the stochastic resonance. I use python for my computations. Thank you very much in advanc... |
Wikipedia states that
a clock that is moving relative to [observer] will be measured to tick slower than a clock that is at rest in their frame of reference
and they explain it using two pictures:
Left: Observer at rest measures time 2L/c between co-local events of light signal generation at A and arrival at A.
Rig... |
Why is it assumed that angular acceleration is 0 when a ball is midair after rolling off a surface with constant velocity?
|
I'm doing a project where I want to calculate the moment of inertia for some objects. I've broken the objects down into simple objects like cubes, spheres, cylinders, etc -- things I know the moment of inertia tensor for. My plan was to take these smaller parts and "glue them together." Since I know the inertia tensor... |
I will outline what I believe to a correct way to go from a Lagrangian of a charged particle in a EM field to Lorentz force via the Euler-Lagrange equations. At the very beginning when I use the EL equation, I will bold what my concern is and return to it after I finish the derivation.
The Lagrangian (in SI units) rea... |
I am trying to understand the presence of complex hopping amplitudes in Hubbard-like lattice models. The hopping term features the so called "Peierls phase":
$$
- t\sum_{j=1}^L \left( c_{j+1}^\dagger c_{j} e^{+i\frac{\Phi}{L}} + c_{j}^\dagger c_{j+1}e^{-i\frac{\Phi}{L}} \right)
$$
where $L$ is the number of latti... |
I was doing some physics problems and randomly came upon a seemingly very intelligent but very rude individual.
His video in question was about magnetism and that there is a vortex and counter-vortex at both ends of a magnet.
This is the video: https://youtu.be/Sn2mAnoQmQk
(The demonstration happens at around the 5min ... |
If I had an iron core solenoid, and was able to measure the force at different distances by say, using a piece of metal attached to a string on a scale, and knew current and other properties of the magnet, would I be able to determine the magnetic intensity, and if so what would the formula look like?
|
I have searched and saw a similar question but i dont know if it's exactly the same.
If I had a rope around earth, let's say a few meters above (and supposing a flat surface, and suddenly dropped it at the same time from all of the points, how would it fall? Or what would happen? I know gravity’s pull is not exactly t... |
We know the following:
Two masses are attracted to one another, as represented by Newtonian gravity
$F = \frac{GMm}{R^{2}}$
Light is massless and bends in the curvature of space-time which can be created by a mass, where the deflection is calculated with Einstein's general relativity and is twice that calculated by N... |
The continuity equation states that flow rate should be conserved in different areas of a pipe:
$$Q = v_1 A_1 = v_2 A_2 = v\pi r^2$$
We can see from this equation that velocity and pipe radius are inversely proportional. If radius is doubled, velocity of flow is quartered.
Another way I was taught to describe flow rate... |
Is there any known calculation for the (~ average) change in entropy between $n$ free-floating amino acids in a cell, at typical physiological concentrations, versus those same $n$ amino acids after they have been translated into a protein by the ribosome?
I imagine calculating the conformational entropy of a protein c... |
Background:
Consider a pure monatomic ideal gas within a closed system undergoing a reversible, isothermal compression/expansion.
The fundamental thermodynamic relation is
$$d U = T d S - P d V + \mu d N$$
which may be rearranged in terms of the entropy and simplified according to our specified path:
$$dS = \frac{P}{T}... |
I am having a discussion on the thermal expansion of a rotor in a supercharger.
The rotor is an alloy—I think it is 7000 series—and is held by a steel shaft.
The rotor is 152 mm long, and if I apply the basic thermal expansion equation to it, I find that it grows by 0.203130 mm if I increase the temperature by 60°C.
Th... |
Can we say the electric charge density of an electron is distributed uniformly over its spherical volume?
|
If I understand it correctly, QFT assigns a field operator to every point in space. For a free scalar field:
$$ \hat{\phi}(\mathbf{x},t)=\int \frac{d^3p}{(2\pi)^3} \frac{1}{\sqrt{2\omega_{\mathbf{p}}}} \left[\hat{a}_{\mathbf{p}}
\exp(-i\omega_{\mathbf{p}}t+i{\mathbf{p}}\cdot\mathbf{x}) + \hat{a}_{\mathbf{p}}^{\dagger}... |
I can't think a formula to actually prove what happens... maybe $=v^2/$? Is the energy of the emitted EMR is higher due to the acceleration of the electron being higher? I am asking this in the context of the Rutherford planetary model of the atom by the way.
|
Question is simple: I was asked to find the average speed of oxygen gas molecules at $T = 300^o K$.
I thought the answer was simple too, as simple as plugging in the equation for $v_{avg}$ which is derivated from Maxwell's speed distribution law, which is $v_{avg} = \sqrt{\frac{8RT}{\pi M}}$ Plugging in the datas, I ge... |
Are there constants that used to be considered fundamental constants but aren't anymore? Are there efforts to show constants (that we currently consider fundamental) aren't really fundamental or that they are related to one another? For example does some theory predict (or almost predict if certain assumptions are ma... |
This is from the book introduction to mechanics by Kleppner D.
Is it some typo, or something i don’t understand?
Does F dt comes down in front of integration?
|
The precession of Earth caused by the Sun and Moon pull like when you breathe super hard on a spinning top, what about massive blackhole which is a point in space conserving it's angular momentum? I know millisecond magnetar precess as it points it jet in our direction periodically not sure about black hole?
|
If Maxwell's demon were able to separate a gas into hot and cold regions without adding energy to the system, we would be able to move a piston between the two chambers until the temperatures equalize again thus creating work out of nothing. This however violates the first law of thermodynamics, therefore Maxwell's dem... |
Say I have a standard 20lb propane tank.
I want to put a protective cover over it, to shelter it from weather.
Can I use a cover that is black or dark colored? Is that dangerous or will it put me at risk?
Most covers seem to be made from leather, polyester, or cotton/oxford cloth.
Various sites will tell you to not pai... |
I have seen many places claiming that the given a collection of topological defects on a 2-dimensional surface, the sum of the topological charges is $2\pi\chi$ (where $\chi$ is the Euler characteristic).
What is the proof of this statement? Can you give me any references for the general case (not in a special case, li... |
Laboratories can cool clouds of hydrogen-1 and helium-4 respectively into Bose–Einstein condensate (BEC), while hydrogen-1 makes up 75% of all atomic matter in the observable universe and helium-4 makes up 24% of all atomic matter. Some of the clouds might never fall into a galactic black hole and always survive while ... |
Why at lower frequencies electric currents do not radiate that much?
|
According to the standard model, would it be theoretically possible to emit protons or other complex particles from the vacuum using the dynamical Casimir effect? Or is it only possible to emit particles such as electrons and photons?
Edit: I effectively have 2 answers here. One says yes for protons, one says no. Which... |
Is it possible to calculate spinning top revolutions per minute?
Will the Spinning top material make a difference to the speed revolutions per minute?
Example : Wood, Plastic, Steel etc
|
The classical Hamiltonian of a damped harmonic oscillator $$H=\frac{p^2}{2m}e^{-\gamma t}+\frac{1}{2}m\omega^2e^{\gamma t}x^2,~(\gamma>0)\tag{1}$$ when promoted to quantum version, remains hermitian. Therefore, the time evolution of the system is unitary and probability conserving. The Heisenberg equation of motion, fo... |
In 2D there is notion of degrees of freedom. D.o.f. defined from correlation functions of stress-enegry tensor:
$$
F(|z|^2) = z^4 \langle T_{zz}(z,\bar{z}) T_{zz}(0,0) \rangle \\
G (|z|^2) = \frac{z^3 \bar{z}}{4} \langle T_{zz}(z,\bar{z}) T_{z\bar{z}}(0,0) \rangle \\
H(|z|^2) = \frac{z^2 \bar{z}^2}{16} \langle T_{z\b... |
I wonder whether or not there is a possibility to find another passive component (with value either $X$ or $Y$) that will change the well known RLC circuit equation below
$$
L\; \frac{\mathrm{d}^2 \; i}{\mathrm{d}\; t^2} + R\; \frac{\mathrm{d} \; i}{\mathrm{d}\; t}+\frac{i}{C}=f(t)
$$
to either
$$
L\; \frac{\mathrm{d}... |
In the book "Fundamental Laws of Mechanics" by I.E Irodov, on page 15, he writes as a footnote,
note the in general case $ |\mathrm{d}\textbf{r}| \neq \mathrm{d}r$ where $r$ is the modulus of the radius vector $\textbf{r}$, and $ v \neq \frac{\mathrm{d}r}{\mathrm{d}t}$. For example, when $\textbf{r}$ changes only in ... |
I've tried figuring this out, but I can't seem to find a way to find it, since I dont have any other information to calculate something. The only thing I could find out was that its possible to use symmetries to find out the center of mass/gravity.
My intuition tells me it should be C however I am not sure. Is there a... |
i am having a problem digesting this circuit. This wire seems wierd and i do not understand how the current flows through this circuit. if we suppose all of them resistors have the same resistance and one needs to calculate the total resistance then how do you go ahead since this wire is blocking me from moving
to the ... |
In an online test the following question was asked:
The motion of a mass is described by $s=2t$ where $s$ is displacement and the force on it by $F=e^t$. What is the work done by it? Their answer was the usual integration of force with displacement by the substitution of $ds=2dt$.
But $s=2t$ describes the motion of a... |
Let's say the system in question is a box with an ideal gas.
It makes sense to me that if this box with a gas is an isolated system then the total energy, being the sum of energies of every particle in the gas, is conserved. But, as it is generally known, it is useless to consider every single particle when describing ... |
I would like to do start doing some basic calculations using DFT. I am interested in solid state physics of strongly correlated materials in 3d or 2d. I prefer free software (no license) which is easy to use. I am interested in DFT as a tool to calculate properties of materials, and I am not interested in learning the ... |
I am doing some experiments with contact angle of liquids on chrome stainless steel and was wondering if in the literature there is already experimental data for contact angles of different fluids on different types of surface. I am certain that this data has to exist somewhere, so I'm wondering if there is some parti... |
If the wavefunctions of two fermions interact, after which they separate can it be that the space parts of the wavefunctions become entangled, just like their spin functions will become entangled, no matter how far they are apart ("transcending" space)? After all, the position is a (quantum mechanical) degree of freedo... |
I'm following Schuller's lectures on gravity and light (this question specifically concerns this part of the video).
Let $M$ be a smooth manifold with a smooth vector field $X$, and let $f\in C^{\infty}(M)$ be a smooth function on $M$. $X$ is a $C^{\infty}(M)\to C^{\infty}(M)$ map so that $f\mapsto Xf$, where $(Xf)(p)$... |
Here is a simplified example
If we consider that both A and B are the same body which is only free to rotate, F is the force acting at the exact same distance from that body in both cases, with the same magnitude and over the same period of time, will the body end up in the same ending position in both cases?
In other... |
Electromagnetic oscillations that have incoherent sources do not manifest any oscillatory or interference patterns. Only when the sources are distilled by appropiate filters like prisms is the oscillation nature of the field observationally manifest
Neutrinos sourced from the sun are presumably being emitted with no sp... |
On the MIT OCW for engineer dynamics the cart pendulum problem is solved by using the Lagrange Method here. This is a 2D problem, so rotation only occurs on the Z axis. While obtaining the rotational Kinetic Energy that is defined as:
$V_{r} = \frac{1}{2}I_{zz}\dot{\theta}^{2}$
Where $I_{zz}$ is the zz element of the i... |
How can we explain the bending of light when it moves through different optical media by Maxwell's equations treating light as an electromagnetic wave?
|
As I understand it black holes have the highest density of entropy per area (and thus per volume for spheres at least) of any form of matter and spacetime.
Also we expect the far future of our accelerating universe to asymptotically approach heat death with every particle infinitely spaced.
If at every timeslice entrop... |
We can derive easily the expression for tension and velocity for a particle in vertical circular motion. We know that in a string tension occurs when the attached object pulls the rope away from the point where the rope is rigidly attached.
We see that when $\theta$ is acute then there is a radial component of $mg$ wh... |
I all, I am struggling to grasp the notion of gauge invariant when talking about an object like the canonical momenta $\frac{\partial L}{\partial \dot{q}_i}$ or kinetic momenta $m\dot{q}_i$.
I am very comfortable with gauge theory in the field theory context, starting with a Lagrangian, requiring its invariance under a... |
I know when two metals are in contact, the Fermi level must line up, somewhere between the two original metals for thermodynamic equilibrium.
When this happens, I wonder how much does the Fermi level change.
For example, what would the Fermi level be if 1 mole of copper and 1 mole of lithium are in contact at $T = 0\ {... |
I am trying to understand a part of I.E.P.'s answer here.
I.E.P. states that one can see from the following Hamiltonian,
$$
H = \frac{1}{2m}|{\bf p}+q{\bf A}|^2 +q \phi \tag{8.35}
$$
that the magnetic field does not work on the charged particle, and thus does not contribute to the energy.
How can one see that directly... |
As far as I understand it general relativity does not explain the origin of the inertial mass $m_i$ in Newton's law of motion $\vec{F}=m_i\ d\vec{v}/dt$ but rather it simply applies the concept to curved spacetime.
For example if we have a particle with inertial mass $m_i$ and charge $q$ moving in flat spacetime in an ... |
I'm trying to figure out what temperature actually is, and there seem to be a lot of answers floating around:
average kinetic energy per degree of freedom
a statistical parameter of the Boltzmann distribution
partial derivative of energy with respect to entropy
a unique parameter that governs the black body radiation ... |
I was taught that stress is the restoring force per unit area (let us assume a rod). This stress is developed on order to resist the motion of the rod. My questions are as follows :
If the rod is subjected to equal and opposite forces why is stress developed as the rod has 0 net force acting on it
My reasoning : the ... |
I never able to wrap my head around alm term used in expression
If you know the expression, kindly explain but also give textbook references. It would be helpful.
|
I know that operators in quantum mechanics act on states (kets, assumed to be normalized), and return another state. So, an operator such as $\hat{p}$ when acted on a ket $|\psi\rangle$ will give me another ket $|\phi\rangle$. Thus, $$\hat{p}|\psi\rangle = |\phi\rangle.\tag{1}\label1$$ Also, $\langle x|\psi\rangle =\ps... |
Consider two cases in a chamber in which gases are filled on both sides of a partition which acts a semi permeable membrane :
1.Hydrogen is filled on one side of the partition and it can move through the semi permeable membrane.Hence it will flow till the pressures on both sides are equal.
2.Next,I have hydrogen on on... |
I was studying the book of Hartle on general relativity. In chapter 9, "The Geometry Outside
a Spherical Star", he suddenly introduces a metric named Schwarzschild metric and then goes on describing the geometry it produces. I did not quite get how exactly this was a metric generated by a spherical start. There must be... |
People often talk about different forms of energy like thermal energy, chemical energy, nuclear energy, etc. as belonging to the internal energy of a physical system. However, I can't really remember having encountered these in rigorous treatments of thermodynamics. I know that the amount of internal energy of a system... |
A sarcomere is the contractible portion of the muscle cell. And here is a figure of three sarcomeres in series before and after contraction:
I was taught that the thick fiber, myosin, pulls on the thin fiber, actin. I am confused as to how contraction can happen because it seems that there is a tug of war going on bet... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.