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In the theory of open quantum system, we make the markovian approximation when the timescale of the memory of the reservoir is small. But this timescale is measured with respect to the characteristic time scale of the quantum system.
How to calculate this characteristic timescale for an arbitrary quantum system with gi... |
Suppose I have some equations of motion for the variables $x(t),y(t)$
\begin{align}
0&=\ddot x + b(t) \dot x + V_x(x,y)\,,\\
0&=\ddot y + b(t) \dot y + V_y(x,y)\,,
\end{align}
where the potential $V$ has a saddle point at, say $x = y = 0$. Is there an efficient formalism to compute set of initial conditions $x(0),y(0),... |
Background The fundamental representation of ${\rm SU(N)}$ is denoted by ${\bf N}$ and the conjugate of the fundamental is denoted by ${\bar{\bf N}}$. If the representation ${\bf N}$ is related to ${\bar{\bf N}}$ via a similarity transformation (i.e., equivalent), ${\bf N}$ is called a real representation. For example... |
I used the formula
Current=charge density× e × area × drift velocity
i.e. i=neAV
So this yield that drift velocity inversely proportional to area of cross section
But the answer to this question is that drift velocity don't depend on cross section
Please explain why can't I use this formula
|
I'd like to study a class of systems which are (essentially) coupled electromagnetic/acoustic oscillators which can act as antennas for an electromagnetic field, but also can vibrate mechanically with resonant modes in a similar range as the electromagnetic field. I'm interested in calculating various properties like ... |
I was reading the book "Advanced Stellar Astrophysics" (William K. Rose, 1998) and I came across a different approach to deriving the hydrostatic equilibrium equation. First he defined the total energy of a static, spherical star,
$$
E = \int udM - \int \dfrac{GM}{r}dM, \tag{1}\label{1}
$$
where $ u $ is the internal e... |
If the piston shown above moves upwards a distance 1 m the shaft work (according to the textbook solution to a related problem) is 1334 J. Shouldn't the sign of work be negative because the shaft moves upward (positive z direction) and the force is negative? According to the sign convention used by the textbook, work ... |
If two neutrinos are entangled somehow--say, for instance, by being created in the same reaction--would their flavor (Tau, Muon, Electron) be enangled, including in their oscillations between the three? As such, when one has its state measured, will the other one's be the same? What reference frame would the collapse o... |
That may sound very silly questions but believe me I'm unable to understand that .
I'm unable to visualise how solid can be said to have distinct boundaries . Please help me so I can make the picture of it in my mind .
If I'm missing something related to question please let me known. Thank you!!
|
I am trying to understand the definition of an anisotropic dielectric media. I think I understand the definition in terms of the susceptibility tensor:
$$
\begin{pmatrix} P_{x}\\ P_{y} \\ P_{z}
\end{pmatrix}
= \epsilon_o \, \begin{pmatrix} \chi_{1_{xx}} & \chi_{1_{xy}} & \chi_{1_{xz}}\\\chi_{1_{yx}} & \chi_{1_{yy}} &... |
I'm working on a problem from YK Lim's "Problems and Solutions on Mechanics". It is Problem 1016. Here is the statement of the problem:
A mass $m$ moves in a circle on a smooth horizontal plane with velocity $v_0$ at a radius $R_0$. The mass is attached to a string which passes through a smooth hole in the plane.
a)... |
For a perfectly conducting and perfectly dielectric interface, I understood that tangential component of electric field is zero and continuous. But I have read that the normal component of magnetic field is also zero. I have read this in the chapter of guided waves between a pair of infinite parallel conducting planes.... |
How do electrons around adjacent atoms in a crystal lattice form pair bonds when they are both negative and should repel each other?
|
I just need an answer in a paragraph . I will be very grateful if i get a quick answer
|
I'm trying to figure out the force exerted on blocks positioned on an angled rail due to gravity. This is the scenario I have (apologies for the poor graphic):
where each block (red square) is equipped with a wheel (black circle) which is fitted on a rail (black lines). The top section of the rail is angled at 50 degr... |
These days I learn about the lattice gauge theory, and in particular learned when one naively discretizes the fermion action, doublers, superfluous poles for a propagator, emerge. I wonder what issue the doublers cause in practice, and how harmful they are.
On the other hand, these doublers are partially admitted in th... |
My textbook states
Notice that since $PV = \text{constant}$ and $\frac{V}{T} = \text{constant}$ for a given
quantity of gas, then $\frac{PV}{T}$ should also be a constant.
I tried to prove this, but no success:
$$PV = a$$
$$\frac{V}{T} = b$$
$$\frac{PV^2}{T} = ab$$
$$PT = \frac{a}{b}$$
But I am not able to cook up ... |
The Eddington expedition in 1919 proved Einstein's general theory of relativity.
[Eddington] argued that the deflection, or bending, of light by the Sun’s gravity could be measured... because Einstein’s theory predicted a deflection precisely twice the value obtained using Isaac Newton’s law of universal gravitation..... |
Do scleronomic constraints and scleronomic systems mean the same? Also, are the generalised coordinates of a scleronomic system explicitly independent of time?
|
The text from book is:
1. Electron leaves negative terminal of the battery and
enters the right end (N-type material) of the diode.
2. Electron then travels through the N-type material.
3. The electron nears the junction and recombines and
becomes a valence electron.
4. The electron now tr... |
At 5:31 of this video, professor Moungi Bawendi says that we could choose any kind of interpolation we like for the temperature scale, and all of thermodynamics would still be 'functionally' the same. This got me curious, for how the thermodynamic relations such as the ideal gas law and others would change as a consequ... |
Moment of inertia isn’t a moment of force, but it is a kind of inertia, so wouldn’t it be more correct to say “inertia of moment”?
|
In the standard courses of classical mechanics inertial reference frame is defined as a frame with respect to which every free material point, i.e. not interacting with other bodies or fields, moves uniformly.
Then the first Newton law says that inertial frames do exist.
I realize that the notion of inertial frame is a... |
Palti writes in his introduction to the swampland (page 39) that a charged black hole (BH) could discharge itself, when the Hawking temperature
$$
T_H=\frac{R_+-R_-}{4\pi R_+^2}
$$
($R_+$ and $R_-$ the outer and inner horizons of the BH) is bigger than the mass $m$ of the charged particle with charge $q$, because then ... |
Consider a $n$ identical copies of spin state $|\phi\rangle=\frac{1}{\sqrt{2}}\left(|\uparrow\rangle+|\downarrow\rangle\right)$. Now we measure if the spin up or down. According to MWI, there always exists a universe so that all copies of spin point up or down, and also universe with wrong statistics if $n$ is large en... |
If we have a sound wave that hits a surface and is observed after it has done so, have its frequency and amplitude changed?
|
In the double slit experiment we see that light waves can interfere with themselves to create interference patterns made of constructive and destructive interference. However, when we observe light before the slits, the wave function collapses and light acts as a particle, generating columns of light instead of the int... |
As torque is the only reason for angular acceleration but... When radial force act on a body it automatically become zero as it passes through center
And only thing left is tangential force which is responsible for the angular acceleration as torque is there. I want to know is any non tangential force on a rigid body c... |
If Magnetic flux is the strength of magnetic field that passes an unit area, (thereby flux PER unit area),then why is it given in units of $T m^2$ and not $T m^{-2}$?
|
I conducted an experiment where I have to align two bar magnets so that both ends are “north - south” and tape them together. Then, I have to drop them through the center of a coil of 400 turns
Results from the voltmeter came out like this.
But, I don’t understand why there are 3 peaks since when I tape them in the “... |
Isn't it just 1 coulomb of electrons passing any cross section per second? Why is it involved here in magnetism?
|
I want to know what happens to angular momentum when velocity is non tangential, and if non tangential velocity have tangential component and some radial component, then how we got
L = Iw
Where I is moment of inertia and w is angular velocity at certain time (say't')
|
Hey I want to find the force of the friction of an object that slip on a inclined plane. The only thing I know is that the object has a 5N gravitational force. I don’t understand how can I do that because I don’t have any distance. I thought that it was the same force as the gravitional force but it seems false.
|
A charge $q$ nears a current-carrying wire. How does $q$ move? Specifically, what is $\vec{r}(t)$ for $q$?
I've found the direction of some of the forces acting on the charge $q$:
Using the Biot-Savart Law and Coulumb's Law, I can also find the Magnitude of the Magnetic and Electric Fields. I've used a suitable Amper... |
In Greene's video: https://www.youtube.com/watch?v=2pV20KuDucs
In the video Greene describes a fairly well-known thought experiment. A person is in a rectangular box floating in space with a laser mounted on middle of one wall. The light beam hits the middle of wall opposite.
Then the box is imagined in free fall where... |
So, it is very clear that mass less things have net force on them as zero (0). Here the string is a mass less string so, the net force on it must be zero right!
The tension $T$ (at mass $M$), is for balancing the mass $M$, so who is cancelling the T at the ceiling, so that net force on the string will be zero, as the... |
Schwarzschild original metric solution can be found here in equation (14): http://old.phys.huji.ac.il/~barak_kol/Courses/Black-holes/reading-papers/SchwarzschildTranslated.pdf
Hilbert's metric solution is the one we are all familiar with, and the one that wikipedia shows under the name "Schwarzschild solution": https:/... |
Perhabs my perspective of string theory is wrong, but I have no idea how the following works:
A string representing a single fermion (like an incoming electron) splits into an other fermionic (outgoing electron) and an outgoing bosonic (photon-like).
The photon means a bosonic mode , but it only appears on an outgoing ... |
Consider a front-wheel drive car that is speeding up on a circular track of radius $R$. The static friction force has a radial component and a tangential component. At some point the speed will become too high for the car to stay on this circular trajectory. At that point the radial component of the friction force will... |
I read on Wikipedia that right-circular cylinder shape helps reduce surface area of the former IPK, but could not find an explanation as to why. So how does such shape helps reduce its surface area? Wouldn't a spherical shape be better for that purpose?
|
Since there is a transverse Fresnel–Fizeau effect according to
Jones, R. V. (1972). "'Fresnel Aether Drag' in a Transversely Moving Medium". Proceedings of the Royal Society A. 328 (1574): 337–352. Bibcode:1972RSPSA.328..337J. doi:10.1098/rspa.1972.0081.
and
Jones, R. V. (1975). "'Aether Drag' in a Transversely Movi... |
I know that in polar coordinates, it is
$\frac{\partial \,{{\mathbf{e}}_{r}}}{\partial \theta }={{\mathbf{e}}_{\theta }}$ and $\frac{\partial \,{{\mathbf{e}}_{\theta }}}{\partial \theta }=-{{\mathbf{e}}_{r}}$
where ${{\mathbf{e}}_{r}}$ and ${{\mathbf{e}}_{\theta }}$ are the basis unit vectors.
Anyway, using the definit... |
I have just started reading some research papers(nuclear) and I am getting really confused between the above two representations.
Please help me and kindly use layman language.
|
As I understand it in Non Relativistic Quantum Mechanics bound states are only allowed at certain energy levels, and that this is the case for any potential that has bound states. Also for some potentials, such as a finite potential well if the energy is lower than the energy at the top of the well then the state is b... |
I am going through Feynman and Hibb's emended edition of Quantum Mechanics and Path Integrals.
Going through chapter 2 made me realise I didn't fully understand infinitesimals, I was hoping someone could give some clarification. My current understanding is that an infinitesimal quantity is an infinitely small quantity ... |
In my E&M lecture, the professor said infinitely large systems (infinite parallel plate, infinitely long line charge, etc.) have zero/constant potential at infinity. Meanwhile, finite dimension systems (as long as the system does not extend to infinity) do not necessarily have constant/zero potential at infinity. There... |
In General Relativity an object on the surface of the Earth feels a force from the Earth due to the surface of the Earth's constant acceleration through space or space-time.
From what I've heard time is also at a fixed rate on the surface of the Earth.
The object cannot reach certain velocities due to Special Relativit... |
Hello could someone please check if my understanding of 'collapsing into eigenfunctions' is correct?
Say we have an observable, given by a linear self-adjoint operator $A$ and then we have $\{\psi_n\}_{n\geq 1}$ as a basis of eigenfunctions, such that $A\psi_n=c_n\psi_n$, for $\mathcal{H}.$
Suppose I have a normalised ... |
I'm reading the book Physics from Symmetry by Jakob Schwichtenberg. In part II the author explain the Lie group theory and in particular he treat the $SU(2)$ group. At a certain point the author tells us that $SU(2)$ is the covering group of the Lie algebra $su(2)$ and this involve that every group with that Lie algebr... |
A nautical mile is the distance traveled in moving through one minute of latitude. A ship which is sailing at a speed of five knots travels five nautical miles in one hour. Two hundred years ago, the speed of a British naval vessel was determined by lowering a small sea anchor which was called a log, and then measuring... |
We say that internal energy is a function temperature and volume [ $U(V,T)$], and other times when we use the Gibbs free energy as our potential, we say that it is a function of temperature and pressure $[ G(T,P)]$ .. but how? How do we decide what is a function of what?
One possible reason that I hypothesized for this... |
First of all I would say that I'm not a physicist, but I have recently been given the task of distinguishing a hexagonal close packing (HCP) from a face centred cubic (FCC) arrangement in a set of 3D data. The data essentially form 3D probability maps and may contain different arrangements of spherical densities.
This ... |
I am curious as to how forces move when a system is in motion. This was never fully explained in my physics classes at university. Let me explain:
I understand the Newtonian (classical) physics that there are equal and opposite forces in play. So when I am standing the force I am exerting on the ground due to gravity ... |
I'm sorry if this is a trivial question, I'm trying to understand the Rydberg formula and unsure if there are different values for the Rydberg constant?
According to Wikipedia's articles about Hydrogen spectral series, Rydberg formula and Rydberg constant, there are two different Rydberg constants:
$R_{\infty} = 1.097... |
Consider a one-dimensional problem with a Hamiltonian
\begin{equation*}
H=\frac{p^2}{2m} + V(x)
\end{equation*}
where $x$ and $p$ are the position and momentum operators, $m$ is the mass and $V(x)$ the potential. $x$ and $p$ are the canonical position and momentum which satisfy that $[x, p] = i\hbar$. In terms of $p$, ... |
Faraday's law states,
$$emf = \oint \mathbf{E} \cdot \mathrm{d}\boldsymbol{l} = - \frac{\mathrm{d}}{\mathrm{d}t} \int \mathbf{B} \cdot \mathrm{d}\mathbf{s}$$
The typical surface we see used to elucidate this law is a single-turn coil of wire like below (purple). Where the surface (green) is a 2-dimensional surface in... |
Suppose I have 2 charges (+q and +Q) which remain fixed and are placed at a seperation R. They will have some Potential Energy which is kQq/R.
So I wanted to ask that if the charges are not fixed then they will exert repulsive forces on each other and due this Force they will move away from each other right?
So how cou... |
As we generally deals with inertial frame of reference and non inertia frame of reference, but what if a body is non-uniformly Accelerate
What do we do to make newtons laws still valid in later frame of Reference
|
For spin-1/2 particles (like electrons), is there a limit of their total angular momentum? Since J = L + S, (I'm imagining the vector model of the atom), if L is really large, could electrons have very large total angular momentum J? Thanks!!
|
So I read from a book that if a charge is injected anywhere in the conductor it must come over to the surface.
But when I read another paragraph from the same book, it was given that when a charge +Q is placed at centre of a spherical conducting shell, a charge -Q will appear on its inner surface and +Q on its outer s... |
Let's say I have a canonical partition function for the canonical assemble related to the Helmholtz free energy $A$, given by
$$A=-kT\ln Z$$
Now, I want to derive thermodynamical quantities, like the internal energy $E$, pressure $p$ and whichever thermodynamic quantity I want.
How do I go about this?
I know any thermo... |
During a QFT course, we were deriving the Dirac equation using the relativistic quantum mechanics' approach. Dirac was well aware of the Klein-Gordon $$\frac{1}{c^2}\frac{\partial^2}{\partial t^2}\psi-\nabla^2\psi +\frac{m^2c^2}{\hbar^2}\psi=0$$ which can be derivated from the energy-momentum relation of a free particl... |
For 2 coupled electrons, the possible spin wavefunctions are:
\begin{align*}
\chi_{1,1} = \upuparrows,\quad \chi_{1,-1}=\downdownarrows\
\end{align*}
\begin{align*}
\chi_{1,0}=\frac{1}{\sqrt2}(\uparrow\downarrow+\downarrow\uparrow)\quad(symmetry), \ and\quad\chi_{0}=\frac{1}{\sqrt2}(\uparrow\downarrow-\downarrow\uparro... |
Suppose we have two masses, $m1$ is on the origin and $m2$ on the positive $x$ axis.
We also define a unit vector from m1 to m2 so that the force from m2 to m1 is $$\vec{F}_{12} = -G\frac{m_1m_2}{r^3}\vec{r},$$ and the force from m1 to m2 is $$\vec{F}_{21} = G\frac{m_1m_2}{r^3}\vec{r}.$$
If we now define the potential... |
Elementary particles such as the electron are quantum mechanical fuzzy objects described by quantum states or wavefunctions. They are not classical billiard balls with some fixed radius.
Can we assign a notion of a natural "size'' of the electron irrespective of the state it is in? The only length associated with the e... |
We know that two or more static charges exert Electrostatic force on each other.
But due to the Force they will repel or attract each other and thus move (The charges are not fixed).
But we know that moving charges also produce magnetic field or We can say that moving charge exert magnetic force.
So while solving for t... |
I'm learning a little bit about path integrals by myself lately and notice something quick curious. So far, I've learned that path integrals have many applications in physics, including quantum mechanics, quantum field theory, condensed matter physics and so on. Also, I commonly see discussions on how path integrals al... |
The question clearer: Is the infinitesimal cube the absolute smallest infinitesimal volume?
(Sorry if people thought that it meant: "Is it possible and is it done in daily life to use anything other than the Cartesian volume element?" : I know the answer to this is of course yes and I know it's usefulness. But please n... |
I notice when I buy aluminium sheets (the kind used for wrapping food) they come in straight, smooth rolls. Once I use them though, they become wrinkled, and they are impossible to un-wrinkle. Image of a wrinkled sheet:
Why is this the case? Only thing I can think of is the Second Law of Thermodynamics, but I can't se... |
Why is the tension in the string different in the diagram below?
Why can't we use the same tension for both the strings as we usually do in Atwood system?
|
If there is a cavity inside a conductor and a charge is placed within it then what exactly happens?
I've read in one book that the charge in the cavity induces a charge (the induced charge is opposite in nature obviously) on the outer surface surface of the cavity. Here is the exact picture. (It is from a pdf which I d... |
I'm having a hard time to understand how many same size black cubes would be in order to pull up the bottom black cube in to the water. I know water level is important but I believe there must be a way to calculate this. please refer to the picture for clarification
the black cube is out of the water and I'm trying t... |
I was reading the mark scheme for 2020 Cambridge A-level physics when I came across a question that reads
The stars S1 and S2 rotate with the same angular velocity ωabout a point P, as illustrated in Fig. 1.2.
Point P is at a distance xfrom the centre of star S 1.
The period of rotation of the stars is 44.2 years.
And ... |
Some of the wavelengths of light that are emitted from the sun will be absorbed by atoms in the outer layer of the sun and also the atmosphere of the sun, and we see this as absorption lines in the spectrum. Now, this absorbed radiation will indeed be re-emitted again, so one might think that these emission lines shoul... |
For a game I'm programming I'm looking for a kind of realistic mechanic for simulating the tearing apart of objects. Let me explain:
I have a given point $p$ in a 2-dimensional space (possible later also more dimensions so a solution should be scalable, which i assume is not the problem) and I have a number of forces $... |
Examples that will further explain the relationship of density to mass and volume, when mass is uniformly distributed.
|
I am trying to derive the radiative transfer equation for a three-level system, which is supposed to be given by:
$\frac{dI(\omega,x)}{dx}+N [\alpha\rho_{11}-\beta( \rho_{22}+\rho_{33})]I(\omega,x)=\beta(\rho_{22}+\rho_{33})$,
where $I(\omega,x)$ is the specific intensity by radiation emitted due to a $|3>$ to $|1>$ tr... |
When the magnet, starting with the north pole, goes towards a coil of wire (maybe a solenoid???) the magnetic field within the wire changes polarity in order to repel the north pole. This is so that work has to be done against the magnetic field in order for that work done to be converted into electrical energy.
When t... |
Find the degrees of freedom of a rigid body moving parallel to a fixed plane surface.
I know the definition of degrees of freedom which meant we need minimum number of coordinate to specify something.
Thoughts about this problem: Since the rigid body moving parallel to the plane so we need two coordinates for transl... |
From a dimensional analysis (with $\hbar=1=c $) of the Dirac Lagrangian $\mathcal{L}= \bar{\psi}(i\gamma^{\mu}\partial_{\mu}-m)\psi $ one obtains that the mass dimension of $\psi$ is $3/2$ (i.e. $[\mathcal{L}]=M^4 \Rightarrow [\psi]=M^{3/2})$. However, when one works with a plane wave (e.g. with positive energy), $\psi... |
When giving talks to Laymen, we find out that the M-theory paradigm says that there are 5 (only 5) superstring theory types, 11d SUGRA and M-theory. Curiously, we read regularly the symmetry groups of heterotic superstrings is $SO(32)$ and $E_8\times E_8$ gauge groups. However, reading the bibliography, it is not easy ... |
One of my books and some of my friends say that torque and other angular quantities depend upon the perpendicular distance from the axis of rotation. This, in effect, would mean that translating your origin along the axis of rotation shouldn't change the torque or angular momentum of a body. Yet in another book, there ... |
I was discussing with my friend about electric field lines and he said that:
given a test charge at rest at a point in the region of the electric field the charge will continue to move along the path of the field line passing through that point.
When asked for how reliable this statement was he couldn't say anything ... |
My book has the following question in it as an exercise:
An electrostatic field line is a continuous curve i.e. a field line cannot have sudden breaks. Why not?
I cannot seem to be able to reason for or against this statement.
Can somebody please tell me why they can't suddenly break and if that were to happen then ... |
The transverse waves in a string stores some potential energy per unit length (numerically equal to kinetic energy per unit length) in it due to the tension present. But in I have read that tension is non conservative in nature. How come then we are able to define a potential energy corresponding to the tension? My bes... |
Bekenstein derived the formula for the maximum energy content of a given volume of space by considering forming a black hole from particles each containing one bit of information.
Actually what is meant is that the black hole is formed by patches of space,
each patch with bit of information determining the existence of... |
Does a charged black hole in 2+1D exist? I am interested in a theory of the form:
$$ S = \int d^3 x \sqrt{-g}\big(\cfrac{R}{2} - \cfrac{1}{2}F^2\big) $$
where $F^2 = F_{ab}F^{ab}$.
The field equations are:
$$G_{ab} = 2T_{ab} $$
$$\nabla^{a}F_{ab}=0$$
Imposing a one degree of freedom metric:
$$ds^2 = -f(r)dt^2 + f^{-1}(... |
Does direction change imply angular acceleration. When a non-point mass object changes direction (like a block sliding down a hill of changing slope), why do we not account for rotational $K.E$ when using conservation of energy? It is technically rotating around its center of mass...
|
When having compact dimensions (I guess it is not true with supermanifolds), the gravitacional constant gets diluted in extra dimensional space:
$$G_N(4d)=G_N(Dd)/V(X)$$
However, I presume that the volume is only if the extra dimensions are compact and bosonic. I mean, if the extra dimensions are grassmannian-like, is ... |
In classical mechanics, it is known from Noether's theorem every continuous symmetry gives a conserved current
\begin{equation}
\partial_{\mu}J^{\mu}=0,
\end{equation}
where $J^{\mu}$ (generally) can be written in terms of fields and their conjugate momentum. The conserved charge $Q$ is
\begin{equation}
Q=\int d^3x J^0... |
We're using Townsend's A Modern Approach to Quantum Mechanics for our QM class, and I'm just rereading Chapter 1 right now. Perhaps I'm reading too closely to the first section (in which, really, Townsend's only aim is to motivate the theory and formalism for QM based on the observed deviations from classical theory in... |
I want to do some calculations for anisotropic properties. The software I am using only takes a tensor matrix as an input. Now to my question. I have 3 literature parameters for the properties along each axis x y z. Is it correct that the tensor matrix would simply be a diagonal matrix?
Sorry for this stupid question, ... |
Is it possible to heat a small amount of water, may be a cup of it, only by human force, using a small scale version of a device like Joule used to prove the heat mechanical equivalence, just by inner liquid molecular friction? Can a human, using his/her muscles generate enough energy for
make a cup of water go from en... |
Starting from the bare Lagrangian-density $\mathcal{L} = \frac{1}{2}(\partial^2 - m_0^2) \phi_0 - \frac{\lambda_0}{4!}\phi_0^4$ one introduces the renormalized field and parameters as
$\phi_0 = \sqrt{Z_\phi}\phi$, $m_0^2 = Z_m m^2$ and $\lambda_0 = Z_\lambda \lambda$.
To fix the first two constants one can look at the ... |
Suppose there are two thin rods $Y$ and $Z$ with length $L_1$ and $L_2$ respectively. $L_2$ has larger magnitude than $L_1$. Both rods have same density $p$, cross sectional area $A$, Young's Modulus $E$ and force applied perpendicularly to the cross sectional area $F$.
For simple compression or tension we have equatio... |
I need help approaching the following problem I made up:
A non-point-like block starts from rest at the top of a curved, friction-less hill. The hill's shape -- assume 2D for simplicity -- is given by $h(x)$ -- a function that gives the hill's height as a function of horizontal distance, $x$. The block has known iner... |
Let me post a question from a school textbook sent to me by a friend of mine. The book has no answer scheme and googling the question is not particularly helpful because the answers seem to vary wildly.
Here is the question:
A $8000$ kg engine pulls $5$ wagons, each of $2000$ kg along a horizontal track. If the engine ... |
In this lecture by mit ocw(*), Moungi Bawendi states that we can have some change in our chemical system containing reactants and products by scaled by some $ \epsilon$ amount. Using this set up and the equation which gives chemical potential as a function of pressure (**) he derives the $\Delta G$ as a function of $ \... |
If electric charges are the only ones that can produce an electric field then a positive potential is produced by positive charges or a lack of electrons, is this true? If this is so, how can I calculate how much charge there is at a certain potential?
|
Suppose we have two completely identical universes (for instance in Tegmark's type III multiverse). In both of them, two identical men are sitting behind identical random number generators (RAN1 and RAN2), and they push the "search" button at the exact same time.
My question is: will RAN1 and RAN2 generate the same num... |
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