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There are 4 piezoresistive sensors placed at A, B, C and D.
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Consider the following interaction term:
\begin{equation}
\mathcal{L}_\text{int} = y_{ij}\bar{\ell}_{iL}\tilde{\eta}N_{jR} + \text{h.c.}
\end{equation}
where
\begin{equation}
\ell_{iL} = \begin{pmatrix}\nu_{iL}\\ e_{iL}\end{pmatrix}
\end{equation}
is the standard $\text{SU}(2)_L$-doublet of left-handed leptons ($... |
A supernova explosion on the far side of the Sun ejects a mass with approximately the same mass of the Sun directly at the back side of the Sun. If this ejected mass is travelling arbitrarily close to the speed of light, the advance warning of its approach would be arbitrarily close to zero. After it collides with the ... |
I'm reading 'Waves in an impossible sea' by Matt Strassler - a very good, popular science book, by the way - and he explains that the rest mass of a proton mostly comes from the kinetic energy of the quarks and gluons whizzing around. But I don't understand why there is quite so much energy in there - and why it is exa... |
In the 2007 "String Theory and M-Theory" textbook by Becker, Becker, Schwartz there is the following claim about the canonical first quantization of a bosonic string: the quantization of the mode expansion operators (Virasoro operators) for a bosonic string is
$$L_{m}=\frac{1}{2} \sum_{n=-\infty}^{\infty} :\alpha_{m-n}... |
Context
A classmate and I need to evaluate the different physical factors at play during a game of pétanque. We thought about estimating the importance of air resistance during the ballistic phase first, but we are running into what we think is a problem. After some research, we decided to model air resistance with qua... |
(Cross post from math.stackexchange)
Consider a continuous time biased random walk on a 1D lattice. The random walker walks with rate $k_\mathrm{R}$ to the right and with rate $k_\mathrm{L}$ to the left. The probability $p_n(t)$ of being at location $n$ at time $t$ is then described by
$$\frac{\mathrm{d}}{\mathrm{d}t}p... |
I read a paper on open quantum system, it's about non-Markovian process with memory effects.
They describe a generic model of two qubits interacting with correlated multimode field.
They describe the interaction Hamiltonian as:
$H_i=\Sigma_k\sigma_z^i(g_kb{_k}^{i\dagger}+g_k^*b_k^{i})$,
and describe the unitary matrix ... |
These days, the majority of work in theoretical particle, condensed matter, and AMO physics is about methods for calculating exotic correlation functions, of the rough form
$$G_{ij} \sim \langle \mathcal{O}_i(t) \, \mathcal{O}_j(t') \rangle$$
though possibly also including time ordering, (anti)symmetrization, more oper... |
An ice cube floats in water, with a liquid (less dense than ice) above it. When the ice cube melts will the water level go up, down or remain constant?
|
In the Kaluza klein reduction we can "decompose" the spacetime $M_n$ as $M_n = M_4 \otimes K_d$, in which $K_d$ is a compact spacetime. So, functions like a scalar $\phi(x,y)$ can be decomposed as follows (assuming $K_d$ is a sphere)
$$\phi(x,y) = \sum_n \phi_n(x) Y^{I_n}(y),$$
(just like we can decompose functions in ... |
Why is projectile motion a parabola given that the Earth rotates and a parabola is an approximation to an orbit.
My current thought is that projectiles don't travel in a parabola because if the Earth were not rotating, they would actually, given Newton's Law of Gravity (F=GMm/r^2), be an approximation to part of a very... |
Suppose I wanted to perform a Monte-Carlo numerical simulation of an Ising-like model, with a Hamiltonian of the form
$$
-\beta H = J \sum_{\langle i j \rangle} \sigma_i \sigma_j + g \sum_{ijk\ell \in\square} \sigma_i \sigma_j \sigma_k \sigma_{\ell}
$$
where the latter sum is over square plaquettes. (The particular mod... |
Say I have a U-tube of constant cross-sectional area $A_C$ whose arms are at a distance $L$ apart from each other. The tube contains two different liquids $A$ and $B$ that don't mix, and at first the height of liquid $A$, relative to the line where the two liquids separate, is $h_a$, as shown in the drawing. Now, I'm t... |
In physics textbooks, problems about rolling usually include the assumption that the rolling is without slipping, meaning that $v=R\omega$ throughout the motion, where $v$ is the translational velocity, $\omega$ is the angular velocity and $R$ is the radius. I do not understand the justification of this assumption. Wha... |
In mathematics, an analytic function is defined by its possession of a Taylor series with a positive radius of convergence ($R_c>0$). Notably, certain analytic functions—such as holomorphic functions—exhibit an infinite radius of convergence. This intriguing property allows us to determine the function’s value at all ... |
I have a question about de Sitter cosmological horizons:
In this video by Leonard Susskind (https://youtu.be/n7eW-xPEvoQ?t=2324) he explains the concept of the Poincaré recurrence using particles and the cosmological horizon. However I always thought that matter "falling" into the horizon was forever lost (like the gal... |
I recently engaged in a discussion regarding Planck's relation, which posits that the energy $E$ of a photon is directly proportional to its frequency $f$, symbolized as $E=hf$. The user @Sturrum on a previous post provided an in-depth answer explaining why this relation holds true particularly for sinusoidal functions... |
I'm doing some problems on decay of K-40 with some students, and I'm baffled by the numbers I'm finding. I expected there to be a much greater mass defect for beta-minus decay than for beta-plus, and I'm finding the opposite. In beta-minus emission, we have a Ca-40 nucleus produced, while in beta-positive, we have a Ar... |
What is the name of a pendulum with two parallel string hung vertical to a rod, and giving the rod an initial force would make it swing left and right, doing simple harmonic motion?
What is the mechanism and formulae of it, or its significance/ related works?
|
Say I have a particle travelling in the $x$-direction and breaking into two pieces:
Conservation of momentum in the $x$-direction obviously gives:
$$mv = m_1 v_1 \cos(30) + m_2 v_2 \cos(60).\tag{1}$$
In the $y$-direction, I could write the following:
$$0 = m_1 v_1 \sin(30) + m_2 v_2 \sin(60).\tag{2}$$
Or I could write... |
In electrodynamics for each charge you need to have data for everything in its past light cone. But the union of all past light cones for all charges would be a spacetime volume rather than a spacetime surface? So how do you ensure your initial data fulfills the dynamics, since you need to know the history of each char... |
I am curious about the relationship between torque and how far something gets lifted by say, a motor. Let's say I have a small motor, and I geared it up so that the gear ratio is 10:1.
I use it to lift a brick that masses 2 kg about 20 cm. The change in potential energy of the brick is
$\Delta PE = mgh = (2kg)(9.8 m/s^... |
If $\omega_{ab}$ is the spin connection 1-form, and $\theta^a$ are the tetrad 1-forms, then one has the equality
\begin{equation}
\int \, d ( \epsilon_{abcd} \omega^{ab} \wedge \theta^c \wedge \theta^d ) = \int d^3 x \sqrt{h} K
\end{equation}
where $K$ is the extrinsic curvature scalar, and the second term is the GHY b... |
In the following I have in mind antiferromagnetic spin chains in periodic boundary conditions on a chain of even length $L$.
Consider the spin-$S$ spin chain
$$H = J \sum_{i=1}^L (S^x_i S^x_{i+1} + S^y_iS^y_{i+1})$$
It appears to gapless for all $S$, meaning that the energy gap between the ground state and the first ex... |
This question seems a little broad but in fact it is very specified.
I read a lot of webpages and papers and books about measurement in quantum computing.
But in my opinion, they are just like "go around in circles"
most of them just refer to those mathematical formulas.
What I want to figure out is a concrete examaple... |
In the paper from Felix Fritzsch & Tomaž Prosen (2021), it's mentioned that the ergodic (dual unitary) circuit has an equilibrium value of order $q^{−2L}$.
At large times autocorrelation functions are expected to equilibrate, i.e.,
they oscillate around their long-time average with both the oscillations and the equili... |
According to Newton's Laws of Motion if the net force is zero then the object does not undergo and change in motion or direction. But how when net force is zero, body initially is at rest and torque is not zero, rotational motion is possible? i.e. net force is zero but how is rotational motion possible.
|
Consider a particle in rotational motion with radius r and angular velocity w both varying with time, what is the relationship between the displacement u and w of the particle? $w=\frac{\partial u}{\partial t}*\frac{1}{r}$, $w=\frac{\partial u_{\theta}}{\partial t}*\frac{1}{r}$ or $\textbf{w}=w\textbf{e}_{z}=\frac{\tex... |
I have some issues understanding X-G. Wen's notion of stable mean-field states of spin liquids.
I understand that the slave-boson mean-field theory is reliable when fluctuations on top of it are weak (i.e., the interactions are irrelevant perturbations).
However, in his book (pg. 368) it is claimed that giving the gaug... |
I've just started studying linear algebra.
I had a question while studying an example.
I'm gonna explain the problem.
$$\\$$
$$\\$$
Augmented matrix for a linear system in the unknowns x, y and z is
$$
\left[\begin{array}{rrr|r}
1 & 0 & 3 & -1 \\
0 & 1 & -4 & 2 \\
0 & 0 & 0 & 0
\end{array}\right]
$$
$
\... |
How may I demonstrate in the most simple way that the following system of differential equation form a damped harmonic oscillator ?
$$
\dot x = -\alpha_x x - \omega y \\
\dot y = -\alpha_y y + \omega x
$$
When $\alpha_x=\alpha_y=0$ I easily get the equation of a non-damped harmonic oscillator.
$$\ddot x = -\omega^2 x$$... |
I have a question regarding liquid lens.
how much we have to change the curvature to get an image shift of 30mm?
|
For arguments sake lets say I have a receiving antenna that has been positioned between two large conductive plates. Are there any differences in how that antenna operates (gain, efficiency etc.) when the conductive plates are electrostatically charged (such that a constant electric field forms between the two) compare... |
I'm having trouble understating the following example in section 3.2 of electricity and magnetism by M.Purcell:
In paragraph 2 of the solution, it states that "The combination of these charges produces no field in the material of the conductor". I understand that it produces no net flux because of Gausses law, but why... |
A string of length 20cm is attached to 2 points A and B at the same level and a distance of 10cm apart. A string of mass 5g can slide on the string and a horizontal force F is applied so the ring is in equilibrium vertically below B.
a) Find the tension in the string
b) Find F, the force applied to maintain equilibrium... |
I have come across in the literature Born–von Kármán (BvK) Supercell, which are described as a unit cell that is repeated periodically. However, say in a calculation that is derived using a BvK supercell, which could obtain something of the form:
$$ \frac{1}{N_{BvK}}F$$
where, $N_{BvK}$ is the number of unit cells in t... |
If we solve the hamiltonian of the following form in the SSH model,
You will get an eigen vector of the following form.
I am having difficulty interpreting this eigen vector.
According to this eigen vector, the probability of there being a particle at A site seems to be fixed at 1/2, but I don't understand this par... |
The picture on the left below illustrates what is intended to be a very simple one-dimensional textbook-style radiative heat transfer problem. It is meant to be a pedagogical tool for explaining the greenhouse effect. The idea is that the gray plate is transparent to all of the incoming radiation from the distant hot s... |
Let us assume there's a body with mass $m$ and velocity $v$, at a distance $r$ from another body of mass $M$. The velocity vector is perpendicular to the radial vector. With these values, how do we find the apogee and perigee of the elliptical orbit of the body?
The problem I'm facing here is that we can assume $r$ to ... |
Usually, the ladder operator denoted by $a$ and $a^\dagger$. In some case, people talk about the creation operator and denote it by $c$ and $c^\dagger$. Recently I see another notation, $b$ and $b^\dagger$, and I don't understand why in each case we use with different letters. I believe that there a reason for this.
I ... |
The Kaluza-Klein metric, by reduction, can be written as a $(4+m) \times (4+m)$ symmetric matrix, where $m$ is the dimension of the additional spacetime (if we decompose $M_D = M_4 \times M_m$). It was show by Bryce de. Witt that, if the non-diagonal metric has the form
$$g_{\mu m} = B^I_{\mu}(x^{\nu}) V^I_m(y^n)$$
An... |
When learning about electromagnetism at my university, electricity flow is generally shown as a conductor with a high potential at one end and a low potential at the other and thus charges flowing down that potential gradient.
The charges are said to accumulate at one end until their own potential flattens this gradien... |
What exactly is kinetic energy? I know that kinetic energy is the energy that an object obtains by the virtue of its motion, but I need an exact answer. So, potential energy, like there are three main types, right? Electrical potential energy, gravitational potential energy, elastic potential energy. So, these three ca... |
Is it possible to teleport Fock states using conventional bosons-based platforms in continuous variables? Usually with bosons-based platforms people perform two-mode squeezing, beam splitter, and EPR (Einstein-Podolsky-Rosen) measurements, but they primarily handle teleport vacuum states. Can this protocol be adapted f... |
Given that both electroweak monopoles and the Sphaleron process involve the non-trivial aspects of electroweak interactions, I am curious about whether there is theoretical or experimental evidence to support the idea that electroweak monopoles might influence the occurrence of Sphaleron processes.
|
Using the equation
$$ \tau R = \sigma y \cos \left( \phi \right) \cos \left( λ \right) \tag{1} $$
means that when the angle $\phi$ between the tensile axis and slip plane normal is $90$, $\cos \left( 90 \right) = 0$ so the resolved sheer stress $\tau R$ is $0$. Is this due to fracture? Why is it $0$ conceptually?
|
I was wondering why convex (and concave) lenses do not appear to disperse light. I heard that due to the angle of the faces on either side of a convex lens, which are almost parallel, very little dispersion occurs. However, the source stated that since the angle between the faces of the prisms is much larger, dispersio... |
When fast electrons goes into a target, part of their kinetic energy is converted into electromagnetic radiation, that we call Bremsstrahlung radiation, as they change their velocity. The energy spectrum is smooth because electron can either lose all their energy and stop inside the material or lose only a fraction of ... |
I read that in 1986 Voyager 2 measured the composition of Uranus' atmosphere, which turned out to be composed of $85 \%$ hydrogen and $15 \%$ helium.
It's not clear to me how this relevant amount of He can be present. The force of gravity on Uranus ($8.69 \space \rm m/s^2$) is lower than that measured on Earth ($9.780 ... |
When an object submerged in a flowing fluid, it will experience a drag force due to shear stress and pressure. Now, I read that there is something called "virtual force" as well acting on the body. I don't quite understand where this force comes from or exactly what it is. And is it connected to the drag force somehow?... |
In $\phi^n$ theory in Peskin & Schroeder the superficial degree of divergence is:
$$D = d - V[\lambda] - \big(\frac{d-2}{2}\big)N \tag{10.13}$$
where $d$ is the dimension, $V$ is the number of vertices and $N$ the number of external lines. Take $N$ to be fixed. We have three possibilities:
If $[\lambda] < 0$ then for ... |
Suppose I have a 3d Ising model on a cubic lattice, but one of its dimensions is much smaller than the other two. That is, I have an $L$ by $L$ by $L'$ slab with $L' << L$; in particular, $L'$ will be comparable to $\log(L)$.
I'm imagining periodic boundary conditions throughout. Suppose that $T_{2d}<T<T_{3d}$, so the ... |
The QCD Lagrangian is
$$
\mathcal{L}_{\text{QCD}} = -\dfrac{1}{2} \text{Tr}\, G_{\mu\nu}G^{\mu\nu} + \sum_i^{N_f} \bar{q_i} \left(i \gamma^\mu \mathcal{D}_\mu - m_i\right)\,q_i, \tag{1}
$$
where $\mathcal{D}_\mu = \partial_\mu + ig G_\mu$, the trace has an implicit factor of $1/2$, $G_\mu$ is the gluonic field and $G_{... |
Im learning about Wigner-$D$ matrices and the applications to spherical harmonics. Now I wanted to test my knowledge, but i failed miserably :( (worked on this the whole day). So here is my problem:
I want to calculate the (spherical) multipole moments of an point charge q sitting on the z-axis at a, but rotated about ... |
I'm working on a derivation of the geodesic equation from the action functional. In special relativity, specifically for flat spacetime, we assume that the metric tensor is constant (not necessarily that it's not a function of the coordinates, but that it traces out constant distances between any two points in space si... |
There are speculative explanations for red shift such as the tired light theory, but I am not referring to those. There are three mainstream explanations
Red shift due the expansion of the universe giving rise to a Doppler effect.
Cosmological red shift. The red shift is due to the stretching of light as the universe... |
I'm an experimentalist working with trapped nanoparticles with optical dipole trap experiments. In the experiment, surprisingly I observed that if I periodically modulate (at full depth) the trap intensity at a frequency much larger than the radial trap frequency of the particle, then surprisingly, I can see an extende... |
Suppose we have a rigid body with known length $r$ that is fixed at point $A$.
We also have a force-torque sensor at point $A$.
The body is fixed such that it doesn't move.
We apply forces to point $B$ and get the values from sensor at point $A$.
How can we translate the f-t values at $A$ to f-t values at $B$?
UPD:
De... |
In an infinite square well, potential energy is given below, why is the probability of finding a particle in the position of infinite potential energy zero?
$$V(x)=\begin{cases}
0,& \text{if } x \ \text{in}\ (-a,a) \\
\infty, & \text{otherwise}
\end{cases}$$
The usual explanation is that because at ... |
I am trying to write down the action that is extremized by Kerr-Newman solutions in General Relativity. Specifically, I am interested in parametrizing the Lagrangian by the mass $M$, angular momentum $J$, and charge $Q$ of the black hole. The first instinct of taking the Einstein-Hilbert action and substituting the Ker... |
Edit: the entire question is in the title, the answer should be an amount of energy and a value of energy transfer in some unit, but not knowing enough about physics I don’t know what the appropriate unit would be which is what prompted the explanation below… I am quite surprised by the responses here but I am most of ... |
Good morning,
I am trying to solve the Boundary Layer equations in the stagnation point in order to compute the stagnation point heat flux. In particular, the fluid is:
-A continuum
-In thermal and chemical equilibrium
-Steady flow
-The flow outside the boundary layer is inviscid, and there are no heat transfers
-The o... |
What does the phrase
The wave function is a representation of the abstract quantum state.
Or more generally,
$A$ is a representation of a vector $\vec V $
mean?
What is the difference between a vector and a representation of a vector?
|
Please explain that how the Toppling in a polygon shaped body shifts from one edge to the next adjacent edge while the object is already in motion, but without any sliding and no external force is applied. It will be better if you explain both ways, with and without including CoM.
|
When bicycling uphill, I have noticed it takes a enormous amount of effort compared to just walking uphill. However, when on level ground, bicycling seems to take considerably less effort than walking. Also when bicycling uphill, I have noticed that turning the wheel lessens the effort required to keep the bicycle from... |
Assume $c=1$
So I've been on a bit of a journey trying to derive special relativity by myself and in doing so was analyzing the viewpoint of a uniformly accelerating observer.
I was particularly interested in how a uniformly accelerated observer (hyperbolic worldline) would observe an inertial observer (linear worldlin... |
https://arxiv.org/pdf/quant-ph/0007071.pdf
In Chapter 6 in the paper "A Numerical Study of the Performance of a Quantum Adiabatic Evolution Algorithm for Satisfiability”, by Edward Farhi, Jeffrey Goldstone and Sam Gutmann, it says that if we destroy the bit structure, then AQC on the exact cover problem does not work as... |
I am self-studying the 3rd edition of Goldstein's Classical Mechanics and have hit a roadblock when working a problem (Chapter 3, Problem 20). The problem asks us to consider a planet of mass $m$ orbiting the Sun, but with an additional force (small compared to gravity) given by
\begin{equation*}
\mathbf{F} = -mC\mathb... |
In statistical mechanics class , it is assumed $\Omega(E) \propto E^N$ where $\Omega(E)$ is the number of microstates corresponding to energy $E$ in a system where number of particles is constant and total energy of reservoir and system is constant. The system is in contact with a reservoir and $N$ is the total number ... |
In the topic of Maxwell relations of thermodynamics, my books says
Of all such derivatives, only three can be independent, and any given derivative can be expressed in terms of an arbitrarily chosen set of three basic derivatives. This set is
conventionally chosen as ${c_p}$ , α, and ${κ_t}$. ...
All first derivatives... |
I just learned about conservation of momentum in my mechanics class.
So say we have two objects, one moving towards another at rest.
I know that in an elastic collision with identical masses, the one that is moving will be at rest after the collision. If I'm getting it right, this is because in the instant they hit, th... |
I'm learning quantum field theory. In Peskin & Schroeder, when they derive
$$\int {D\phi(x)\phi ({x_1})\phi ({x_2})\exp [i\int {{d^4}x\mathcal{L(x)}] = \left\langle {{\phi _b}|{e^{ - iHT}}T\{ \phi ({x_1})\phi ({x_2})\} {e^{ - iHT}}|{\phi _a}} \right\rangle } } $$
and what to make it nearly equal to two-point correlatio... |
Book "Atoms, radiation, and radiatuon protection" shows decay modes in appendix.
In case of Au-198, there is only one type of decay β-.
β- : 0.255max (avg 0.079) (1%)
0.961max (avg 0.315) (99%)
γ : 0.412(96%)
0.676(1%)
The difference between max β- value
0.961 - 0.255 = 0.706 doesn't appear in γ ray but there is 0.676.... |
I have a very naive question, actually someone asked it and I can't answer. It simply asks that if gravitational energy cannot be localised (we cannot write a pure gravitational energy momentum tensor) then how do gravitational waves carry energy? I realised I do not understand gravitational waves well.
In addition, is... |
In ref PhysRevLett.131.220404, the author have studied the scrambling in a Radiative Random Unitary Circuit (RUC) -- a RUC that exchanges qubits with an environment at a rate $p$.
It might perhaps be trivial, but the author did not mention how does the swapping operation is performed except
Between layers of unitary g... |
According to the answer on
question 364576
this should be settled. But after looking for clear statements of the current situation on triviality of $\phi^4$ theory, I'm still not sure, because:
In Scalar_field_theory
we find the statement:
"Michael Aizenman proved that the theory is indeed trivial, for space-time dime... |
This is related to my previous question. I am generating images of how long it takes for a double pendulum to flip in different configurations. I was trying to find the shape of where it isn't energetically possible to flip where $3l_1 = l_2$ and $m_1 = m_2$, where $l$ is the lengths of the pendulums and m is the mass... |
I have a couple of questions about de Sitter cosmological horizons. Initially I made a single post containing the two questions, but after some suggestions, I asked them in two separate posts. This one is about vacuum energy in a de Sitter universe:
In this video by Leonard Susskind (https://youtu.be/n7eW-xPEvoQ?t=2324... |
Literally, what would be the physical meaning of kinetic energy in quantum mechanics?
There is kinetic energy operator term even in time-independent Schrodinger equation.
And this operator and wavefunction will give energy eigenvalue. Can I just say this quantity is related to the probability of the particle?
|
I am a member of a group of high schoolers and we've been looking to set our sights on a challenging project to dump some time into. Currently we're investigating how realistic it is to attempt building a small particle collider. We will likely be funded by the high school so money shouldn't be a huge issue.
Really we'... |
If we apply a force on the rim of a disc kept on a frictionless surface the disc rotates but can it be called rolling? Because what I know is that for rolling friction is necessary. Also can I consider the point of contact between the disc and surface be taken as instantaneous centre of rotation?
|
The Pauli equation describes a non-relativistic spin-1/2 particle in an electromagnetic field. The solution is a two-component wave function.
However, what if we have a system of two particles that interact with each other electromagnetically (e.g., two electrons)? In general, the motion of the particles would create e... |
In my book, the first law of thermodynamics is written as:
$$\delta Q=dU+\delta W$$
Now it's strictly written why we have different notations for heat and work and internal energy. It's written that internal energy is a perfect differential while work and heat are not because $U$ is a function of the system's state, wh... |
I am very new to statistical mechanics, so this question might seem easy for you. I am reading from Blundell and Blundell's Concepts in Thermal Physics, and my question is from chapter $4$ (Temperature and Boltzmann factor)
We introduce temperature via the $\frac{1}{k_BT} = \frac{d\Omega}{dE}$. In the derivations $\Ome... |
I've been studying the interference phenomena observed in the double-slit experiment and came across a concept that piqued my interest. It is well understood that for interference patterns to form, the overlapping waves (or photons) must exhibit a degree of coherence. However, the underlying quantum mechanics introduce... |
In the information theoretic treatment of say, the canonical ensemble, one must maximise the Shannon entropy
$$ S =-\sum_i p_i \ln p_i$$
where $p_i$ is the subjective probability for occupying state $\lvert i \rangle$, subject to the constraint that the mean energy is a constant $U$, which for Hamiltonian $H$ can be wr... |
I am looking into ion thrusters and the small amount of propulsion they provide.
I am really new to this, so I want to understand. If we have mass of 1 kg in space and we are able to apply to it a 1 gram-force (which from my understanding would be quite good for some ion thrusters) what would be the effect on that 1kg ... |
In Group Theory by Zee in Chapter IV.2, he discusses the multiplication of two $SO(3)$ representations on p. 207. Suppose you have a symmetric traceless tensor $S^{ij}$ which furnishes a $5$-dimensional irreducible representation and a vector $T^k$ which furnishes a $3$-dimensional irreducible representation, we can th... |
Having recently studied TDPT for masers, I wanted to go back and relax the RWA to see what would happen. What I find is that, assuming all atoms are injected into the maser in an excited state, then the probability of transitioning to the ground state given a time-varying electric field in the maser cavity is:
$P \prop... |
As noted by Mr. Gremlin in this post: How is it possible to accelerate a neutron?
Crudely paraphrasing, subatomic particles with non-zero magnetic dipole moments interact with magnetic fields to give a non-zero potential energy. Such effects may be used to trap neutrons in a magnetic bottle using their magnetic dipole ... |
So our professor asked us to come up with interesting questions on vernier calipers as he taught us about them today.
Obviously I could have Googled some up and gave it to him however for my own sake I wanted to do some thought.
What came to my mind was whether I could create a triple vernier caliper? I.e., a vernier c... |
As I've learned classical mechanics from different sources, I've seen both
$$\frac{d}{dt} \left( \frac{\partial L}{\partial \dot{q}_k} \right) - \frac{\partial L}{\partial q_k} = 0,$$
and
$$\frac{\partial L}{\partial q_k} - \frac{d}{dt} \left( \frac{\partial L}{\partial \dot{q}_k} \right) = 0.$$
Obviously, they can be ... |
Assuming the following: An isolated space, 1 atm pressure throughout, standard surface tension, vapour pressure and no external force like gravity, Can we provide enough impulse to a drop of water (or a bulk of water) at 300K such that it boils due to the sheer kinetic energy? and if so, how much is required?
Would it ... |
If we have a singular charge in a universe and it is not stationary can it produce a magnetic field? Because even though it's moving there will be no relative motion and no electric force will act on it.
|
What kind of wavefront does a water wave (ripples in water) have?
I'm confused since a wavefront is defined to be normal to the direction of wave propagation and joining all the particles in same phase, and I'm thinking of a plane parallel in which the wave (ripples) is transmitted , which doesn't satisfy the first cr... |
I am a bit confuse in the first statement.
I think the statement is implying vapour as 'former' and gas as 'latter'. Am I correct here?
But gas can be liqufied with pressure alone below the critical temperature;
and as for vapour, isnt vapour only depend on temperature? Am i wrong here?
So is there a mistake in the st... |
In a magnetometer, like VSM, we measure the magnetisation of the sample which is the net magnetisation. Is it possible to measure the component of the magnetisation along a specific direction? If yes, what instrument can do this?
|
I have had contradicting answers. My teacher has told me that time period increases with damping. It does make sense in a way because it's harder for the pendulum to move. Furthermore, previous answers I checked also confirm this.
But with the damping it's not just how hard it is for the pendulum to move, it is also ho... |
I had to analyze the emission spectrum of a compact fluorescent lamp and find what elements are present in the lamp, based on the spectrum of spikes in wavelengths. Knowing that in our lamp there was mercury, why aren't all the spikes that are characteristic of mercury showing up in our spectrum and how can we know for... |
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