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When modeling a real inductor, typically the equivalent circuit is the following one:
Source
A series resistance and parallel capacitor is added.
This model works very well to explain the following impedance graph:
Same Source
If I now draw what I imagine would be seen on that inductor whilst being driven by an AC so... |
I'm trying to see tiny movements in a membrane using a laser spot that shines on it, and looking at the reflected spot. I was wondering if it is possible for any plane mirror arrangement to give me some optical advantage.
Moving the screen further away is an option, but not a good one mainly because my laser is divergi... |
Splitting methods are defined to approximate the solution of the differential equation
$$
y'(t) = (X+Y)y(t), \ \ \ \ \ \ \ t \in (t_0,T) \tag{1}\label{eq:1}
$$
where $X$ and $Y$ are non-commuting matrices, as follows:
$$
\prod^L_{l=1}\left(e^{ \tau a_lX}e^{ \tau b_lY} \right) \approx e^{\tau(X+Y)} \tag{2}\label{eq:2}... |
So the Cauchy/Lorentz distribution is often used to describe distributions in physics (e.g. resonance). But theoretically, the Cauchy/Lorentz Distribution does not have a defined mean and variance, and the central limit theorem is not applicable.
What consequences does this have on the statistics that can be performed ... |
I have the decay equation
$$p + π^− → n + K^− + π^+.$$
I have been told the force of interaction in this is the weak nuclear force, but I was looking for an explanation of how you can work that out having been only given the decay equation.
|
I had a doubt. This may be really basic, but yeah.
Say there's a bulb. The bulb is connected to a battery by two wires. One wire connects the negative terminal of the battery to the bulb (let's call it wire A), while the other connects the bulb to the positive terminal of the battery (wire B). The switch connected to w... |
I understand that when an ideal gas is compressed using a piston, the piston does work on the gas and increases the gas's kinetic energy (so temperature). However, I do not understand why a gas is cooled when the piston is lifted and the gas expands. Where does the kinetic energy of the go?
A real life example of this ... |
The supplementary section of a paper I am reading uses the "substitution" property of the Dirac delta function :
$$\mathbf{v}\left(\mathbf{x}_j\right)\delta\left(\mathbf{x}-\mathbf{x}_j\right)=\mathbf{v}\left(\mathbf{x}\right)\delta\left(\mathbf{x}-\mathbf{x}_j\right)$$
I've never encountered this before.
How does one... |
I apologize if this is a dumb question but I have really thought about this a while and I can’t understand it. I have tried to prove this using the power series of the exponential function but I did not get anywhere. I really don't understand why the first term is there. So can someone help me understand why the follow... |
Brans-Dicke theory with small values of parameter $w$ are said to be ruled out by solar system general relativity tests like the Shapiro time delay test and the deflection of starlight by the sun.
But the calculations based on Brans-Dicke theory assume the Sun is alone in an empty universe. This is not a reasonable ass... |
I'm currently taking my first course in general relativity, and I was wondering:
We know from the schwarzschild metric that for a (far away) observer looking at an object falling towards a black hole, he would see the object gets closer and closer to the schwarzschild radius, but never cross it because of the singulari... |
I am looking at papers that discusses existence of dark states, e.g. the classic "Laser cooling below the Doppler limit by polarization
gradients: simple theoretical models".
Is it true that center of mass motion is essential for darkness?
Is there a precise formula to express darkness condition in terms of the multipa... |
I am currently in high school and trying to gain some conceptual clarity on entropy and the second law of thermodynamics which led me to read various answers on this forum and i have referred some other texts as my textbook does not explain much about the differences in irreversible and reversible process. I have writt... |
This might be a very novice question but i got confused over derivation of $C_p-C_v = R$ which is derived using $dQ= n C_p dT,$ which is valid only for isobaric process. Thus $C_p-C_v = R$ must also only be valid for isobaric process only?
|
This is a question related to the an answer for this question regarding boosts which make $\vec{E}$ parallel to $\vec{B}$ in the boosted frame.
I do understand the approach and the cases 1a and 1b. However, I don't see how we arrive at the condition for $\alpha$ for case 2.
I tried to make use of the cross product of t... |
Ordinary Yang-Mills gauge theory giving spin 1 gauge bosons can be mathematically described by connection 1-forms and curvature of principal bundles. I wonder, what the proper mathematical description of higher spin gauge theory is, so whether there is also some differential geometric description.
|
I deal with analysis of acoustic signals in solids. And after some literature research in physics and mathematic, I have a question about the followings two theories:
Wave equation theory: Imagine I have a simple plane wave $Ae^{j\omega (t-x/c)}$ propagating from medium 1 through medium 2 to medium 3. According to the... |
The bicycle in the figure gained speed and then the feet were pulled back from the pedals. Since no torque is applied to the pedals, the friction force on the rear wheel is directed backwards. However, after this point, there is something that confuses me. Friction forces create a backward acceleration that slows down... |
I was studying rotational mechanics a while ago, and came across the idea of moment of inertia. The moment of inertia of an object describes its resistance to angular acceleration. The definition of the moment of inertia of a point mass about a fixed point is $mr^2$. I understand why the mass of the object dampens the ... |
I get that in QM an observable corresponds to a Hermitian operator. And I also get that not all Hermitian operators will correspond to an observable - with all that $C^*algebra$ stuff. Is there a practical way to check if a Hermitian matrix corresponds to an observable. I did ask ChatGPT which said a Hermitian operator... |
The Klein-Gordon equation describes a scalar field, and the Dirac Equation describes a spinor field. Is there an equivalent equation for a vector field? As well as spin 3/2 and spin 2 tensor fields? Or do you always use other means to describe the evolution of other fields. If so, how do you describe Vector and other t... |
I am studying the quantization of free electromagnetic field using the book "Optical Coherence and Quantum Optics" by Mandel and Wolf (Mandel&Wolf, Chapter 10) and when I started to review the section after find the following expression for the vector potential in terms of a expansion of plane waves (p.468)
$$\boldsymb... |
Three days ago, I put a fully saturated solution of salt in water in an open-top glass jar. I wrapped the jar in a plastic bag in case it exploded, but when I returned in the morning, it had formed ice crystals suspended in brine.
Two days ago, I repeated the experiment with about twice the previous quantity of solutio... |
I am unclear about what is meant by spin quantum number being an inherent number. I understand the spin quantum number can either be +1/2 or -1/2.
So, we can think of the spin quantum number like a arrow pointing upward or downward, and it always have the same magnitude.
What I am unclear about is this: Can there be a ... |
In the drivation of Snell's law for light as EM waves, we have the wave vector components parallel to the interface $k1\parallel$ = $k2\parallel$ as shown in the picture.
From $k_{1x} = k_{2x}$, we have $k_1sin\theta_1 = k_2sin\theta_2$. From the well known equations below,
$$
\frac{k_2}{k_1}=\frac{\lambda_1}{\lambda... |
Suppose we have a network of circuit nodes connected to each other via two-terminal mutual capacitances $C_{m,ij}$.
Is there a recipe for finding the capacitance matrix for this network, and for eliminating certain nodes that are allowed to float?
This question was inspired by Total capacitance from a capacitance matr... |
I'd like to ask about an experiment on atmospheric pressure. To conduct the experiment, we need an empty PET bottle and make a small cut on the lower part of the bottle. A cut no greater than one-half the circumference is acceptable. Then, we press a table tennis ball against the cut to open the cut, being sure to make... |
My teacher asked a question and said to search about it.
We know that the power consumption of the resistance (wasted power) can be obtained by the following formula:
$$\begin{align} P &= I^2R \\
P &= \frac{V^2}{R} \end{align} $$
Now we know that in power transmission lines, electrical energy is transmitted with high ... |
I have questions about differential geometry calculations. If there is any misunderstanding of mine in the contents below, please let me know and help me to fix it.
Let's consider a 3-dimensional spacetime $\mathcal{M} = \mathbb{R} \times \Sigma^2$ ($\mathbb{R}$ for time) and three 1-forms $e^a$ ($a = 1, 2$) and $\omeg... |
I like to soak cookies in large coffee mug for breakfast. As a direct result of this, sometimes I try to soak the cookie in too quickly. The whole story is this:
When I try to soak the cookie in and the coffee is at a lower temperature (around 40-60 C I assume) the soaking happens in a couple of seconds and it's nice ... |
This is something I have read many times that the double slit experiment done with electrons produce the same pattern that we get with light i.e. the electrons undergo superposition similar to that of light waves and thus can interfere constructively or destructively.
But wait! Electrons carry negative charges and so t... |
Good day everyone. When I try to do a second quantization on the hamiltonian, I end up with the following equation,
$$ H = \int \frac{d^3p}{(2\pi)^3} \omega_{\vec{p}} {a_{\vec{p}}}^{\dagger} {a_{\vec{p}}}.$$
According to the notes that I am following,
$$ H |\vec{p}> = \omega_{\vec{p}}|\vec{p} > . $$
But,
$$ H |\vec{p}>... |
Generally, the coriolis acceleration is given as
$-2\vec{\Omega}\times\vec{v}$
Just as $\vec{\Omega}$ or $\vec{v}$, the coriolis acceleration can be rewritten in local cartesian coordinates (edited):
$-(2\omega\Omega\cos{\Theta}-2v\Omega\sin{\Theta}, 2u\Omega\sin{\Theta}, -2u\Omega\cos{\Theta})$
with $\vec{\Omega}=(0,\... |
I tested the special relativity addition formula
$$u_{\text{total}}=\frac{v+u}{1+\frac{vu}{c^2}}$$
and
found that addition of small numbers converges to smaller speed, but bigger numbers to bigger speeds.
For example:
addition 0.5 + 0.5 gives 0.8, but 0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1 gives ~ 0.763
addition 0.00... |
Some objects have a natural frequency. This can be anything from a metal ball to a table, etc. When we hit such an object, it will start vibrating with a certain frequency $f$. Because of damping the amplitude of this oscillation will decrease with time.
In continuum mechanics, an object consists of many particles, whi... |
I am seeing in some academic references that Bernoulli's theorem was applied in venturimeter, bunsen burner, aerofoil lift, carburetor in bikes, sprayer, etc,.. But Bernoulli's equation and theorem was derived based on the assumption that flow of the fluid is streamlined. But I doubt the example applications of this th... |
If a stationary observer, 'A', observes the collapse of a wavefunction, does an observer, 'B', traveling at relativistic speed observe a different collapse of the same wavefunction?
What do all the interpretations says about this topic?
|
Speaking to my friends and family about my job I often receive the question of what quantum mechanics really is.
I always find very time-expensive to explain it with no technical informations and without telling them those silly wrong analogies that go like "I have 2 colored balls, I take and measure the colour, i know... |
Let's suppose that $M$ is spacetime manifold. An observer is then defined as a future-directed, timelike curve $\gamma : I\rightarrow M$, together with a frame field $\{e_{\mu}(\tau)\}^4_{\mu = 1}\in T_{\gamma(\tau)}M$ that satisfies $g_{\gamma(\tau)}(e_{\mu}(\tau), e_{\nu}(\tau)) = \eta_{\mu\nu}$.
I have two questions... |
Let's say we have a rope placed on the line $y=0$ on a flat table in the $(x,y)$ plane. We place one hand on the rope at $x=0$ and $x=l$ and then move our hands together along the $x$-axis so that they are now at $x=0$ and $x=a$. What shape does the rope make, given a specific $a$ and $l$?
If the rope is perfectly stra... |
Let's say there are two bodies, one stationary and the other with a constant velocity. After they have collided, some momentum of the moving body will be transferred to the stationary body. This will result in a change in the momentum of the moving body.
With all this information, can we determine the normal force's ma... |
Let's imagine we have access to a propulsion technology which can move an object, e.g. a space vessel, in one direction without moving anything (such as reaction mass) in the opposite direction. This is, of course, not possible.
I am interested in what contradictions would result from such a technology. We would be abl... |
The classic experiment. First polarizer at 0 degrees, next at 45, next at 90 and light at 1/8 attenuation passes. Imagine you used metal gratings to polarize a source of non-polarized radio waves (say something in the UHF band) in the same manner. Would we expect the same result? Is there any reason to think that this ... |
In common examples and understanding, like bullet firing, higher the velocity the distance traveled will be higher in a given time, but in the case of terminal velocity concept it is said that the drag force is proportional to the velocity (in the stokes law). If so, the object with higher velocity will have difficulty... |
In inelastic collisions, the kinetic energy of the system is not conserved however momentum is still conserved.
How is this possible?
If momentum is conserved than we can write the following equation:
$$m_1u_1 + m_2u_2 = m_1v_1 + m_2v_2$$
Where $u$ represents initial velocity and $v$ represents final velocity.
If squar... |
My doubt is a rather silly, simple one but i cant seem to understand what's wrong.
Let's assume a rocket is moving up with a constant acceleration of $a$, is moving strictly vertically(no gravity turns, etc.) and reaches a height $h$. Obviously the time taken should be
$t=\sqrt{\frac{2h}{a-g}}$(net acceleration is $a -... |
I am attempting to prove the following statement: A positive partial transpose (PPT) state cannot be distilled.
I would like to do so using the following facts:
Let $\rho$ represent a bipartite quantum state. We may write $\rho$ via matrix elements in a product basis, $\rho_{m\mu, n\nu} = \langle m\mu \;|\rho \;| n\n... |
Lets say there are 2 point particles A and B separated by a distance $x_{0}$ whose velocities are $v_{1}$ and $v_{2}$ along the positive X-axis respectively such that $v_{1}>v_{2}$
We can clearly see that at some time, A will over take B.
Now we consider the exact scenario in a different way.
A covers $x_{0}$ in $t_{0... |
According to pascal's law as the pressure applied in a closed container will be equally distributed in all directions, we have a mechanical advantage of pushing the piston of large cross sectional area when we push the piston of small cross-sectional area in hydraulic lift. But my doubt based on the below diagram is
W... |
What interpretations are ruled out by this theorem (such as superdeterminism, Bohmian mechanics, or ensemble interpretations) and does it function similarly to Bell's theorem as a 'no-go' theorem?
|
Let's assume that you somehow created polarized light in a vacuum. Is there any mechanism that can make that light unpolarized down the line?
|
Am I right in saying that accelerations can only be given a sign if a coordinate system is defined in relation to which they are described?
Is this idea applied to any vector quantity?
Is there a guideline for this?
|
I have access to some high quality CFD data that includes 2D and 3D level set functions for simulations of bubbles. Masking the level set function using a heaviside is easy and it is a fast way to get the interface of the bubble.
For some interesting applications to my research I want to see if I can go from the interf... |
When we speak of electromagnetic waves, we think of oscillating waves. But all disturbances need not be oscillating at a frequency. For example, if I take water, I could just lower the bottom plate and cause a cavity at the middle of a pool, and that disturbance would propagate outward as a decrease in amplitude, but n... |
If I start with an $SU(5)$ gauge group and discover that the vacuum is preserved only by matrices of the form $G$
$$\begin{bmatrix}
A & 0 \\
0 & B \\
\end{bmatrix}$$
where the conditions on $A$ and $B$ ($A$ is a $3\times 3$ matrix and $B$ a $2\times 2$) are: that they must be Hermitian, and the matr... |
Studying the photoelectric effect for the first time, and can't find many answers as to why the ratio of electrons to photons absorbed has to be 1:1. Is it possible for an electron to absorb more than one photon at once, even if frequency isn't enough to excite it enough and release it? If so, are there examples of thi... |
For a physics project, I am experimenting with magnetic levitation.
The goal of the project is to levitate a magnet on top of a plate of material. The guidelines for the project are that the plate cannot be magnetic but it should be conductive. I first thought of eddy currents so I got a copper plate about 5 mm thick a... |
I was following the proof in the lecture 13 of Feynman Volume 1 where he proves that the force produced by the earth on a point outside or on the surface of it is equal to force produced by a point mass located at the center of the earth with a mass equal to that of the earth. I am having trouble validating the beginni... |
Electromagnetic waves are generated by accelerating electric charges.
Photons on the other hand, tend to describe something different, specifically the particle nature of electromagnetic waves as detected experimentally.
Is it something like EM waves are like the ripples in water, but photons are like the individual mo... |
I am reading an old paper from the 1970s regarding a line current EM induction. In the paper they say that (under certain assumptions), Maxwell's equations can be simplified to a diffusion equation of the form:
$$\nabla^2E_y = i\omega\mu\sigma E_y$$
They then go on to say that "employing the method of separation of var... |
When unpolarized light travels from air into a glass slab, the reflected light is polarized if the incident angle is equal to the Brewster angle. This is clear to me. However, according to Wikipedia, the refracted light becomes slightly polarized—a concept I find a bit confusing.
My question is what happens when this s... |
Say I have 4 equal point charges in corners of a square. The electric field in the middle is 0.
Now I brought another same charge from infinite hight to the middle of the square. I know the potential in the middle is not 0. The charge needs to move because there is potential difference (assuming 0 potential at infinity... |
The path integral, in the simplest case, usually attributes a classical action to every conceivable trajectory a particle can take between to points in spacetime. This assumes a flat, Minkowski background. Is it possible to use the path integral to attribute a classical action to the formation of one or more virtual pa... |
I need compressed $\rm CO_2$ for a project I'm working on, and am trying to figure out how much volume of gaseous $\rm CO_2$ I get from a given weight of liquid $\rm CO_2$ in canister. As far as I can tell the answer lies in the ideal gas law, but I'm unsure how to set up an expression that would give me an answer. Eve... |
I know that an electrostatic (or magnetostatic) field does not depend on time but I was imagining to put a charge in a region of space. First there was no electrostatic field and then it appears, how does it all happen? There is a variation of the electrostatic field in the instant in which I create the aforementioned ... |
Does force - any kind - have an identity of its own apart from the set of effects it brings about? Or is it just "that which" ... "causes"; does this and that, makes certain things happen, which did not exist previously?
|
If I squeeze hydrogen superhard with 400-500GPa of pressure, it becomes metal so is that solid or liquid? I know gallium melts on my hand and it's metal.
|
A charge is moving at constant velocity along the x-axis.
Question: is there induction occurring, OR, only magnetostatic fields updating as the charge moves at a constant velocity?
Let's say the charge was at x = -0.1 (time t = 1), and now it's at x = 0 (time t = 1.1).
(Please assume that it has been moving with a cons... |
A net point-charge density $\rho_0$ is impressed without speed (no impressed current density) at position r0 at time $t_0$. Relaxation analysis tells us the charge density will decrease exponentially because charges tend to separate them and locate on the material surface.
I'm curious about not just evaluating the char... |
What modifications/corrections are made by the $f(R)$ gravity model on the Morris-Thorne wormhole metric? Specifically, how does the physics associated with the metric change in $f(R)$ gravity compare to the General Theory of Relativity?
|
In my study of quantum mechanics, I've encountered the concept of wavefunction collapse after measurement, followed by the subsequent spreading out of the wavefunction in space. I'm curious to know if there is a maximum speed at which this spreading out occurs.
I understand that the spreading of the wavefunction is gov... |
Is there any limit to the bending of spacetime due to gravity?
I have been reading about wormholes and how they bend spacetime and connect two systems. But if there is no limit to gravity, we can infinitely bend spacetime and it will form infinitely many wormholes which should not be possible, because we will never kno... |
I have a hollow cylinder of a known surface density and a known fracture stress. We can easily calculate the field component normal to the surface and get the pressure by dividing by surface. Alternatively we can use the electrostatic pressure formula.
I don't think these two match, and this is not the first problem I'... |
I'm working on a model where particles with concentration $\phi$ diffuse to an adsorbing sphere. For the non-growing case, I assume a steady-state solution and Fick's second law $\frac{\partial\phi}{\partial t}= D \nabla^2\phi$ reduces to Laplace's equation. With boundary conditions $\lim_{r \to \infty}\phi(r)=\phi_{\... |
A parallel-plate capacitor having plate area $20\,\text{cm}^2$ and separation between the plates $1.00\,\text{mm}$ is connected to a battery of $12.0\,\text{V}$. The plates are pulled apart to increase the separation to $2.0 \, \text{mm}$. (a) Calculate the charge flown through the circuit during the process. (b) How ... |
Familiarity with QM tells us that when an eigenvalue of an operator $\hat{A}$ is degenerate i.e. more than one eigenfunction of $\hat{A}$ has the same eigenvalue, there is usually another operator (or operators) $\hat{B}$ whose action on these eigenfunctions gives different eigenvalues. For example, $\hat{A}$ is the Ha... |
In the article Strange Metals as Ersatz Fermi Liquids
, the authors mentioned in the left bottom paragraph on page 4 that
Furthermore the diverging susceptibility of an order parameter at a quantum critical points does not necessarily imply that one of the proximate phases has static order for the corresponding observ... |
Are Andrews Curve (isotherms) for gas-liq phase change less dense for low values temperature and more dense for high value of temperature?
I came up with this because of Clausius Clapeyron Equation with says dP/dT ∝ 1/T. For low values of T change in pressure i.e dP is more and thus the isotherm will be spaced further... |
During time-resolved photoluminescence studies in perovskite materials, one sometimes says that it has a microsecond carrier lifetime. What do we actually mean by that? Where does the excited electron reside: in the conduction band (CB) or trap states inside the bandgap?
If it is CB minimum, it should instantly decay d... |
I find in the liuterature (e.g. Landau & Lifshitz [1]) that the entropy in a microcanonical ensemble is given as:
$S = k_B \log(\Omega),$ where $\Omega$ is the mutiplicity of microstates (Landau uses the notation $\Delta \Gamma = \Omega$), i.e., the entropy is given by the boltzman constant times the logarithm of the t... |
I struggle to reconcile two aspects of classical gauge field theories, stated informally (and vaguely, I admit) as follows:
Changing the gauge does not have any physical effects because the freedom to choose a gauge only reflects a redundancy in the mathematical description of physical reality.
Gauge fields do have a ... |
Is there any analytical approximate (newtonian, postnewtonian) formulae for the gravitational field/potential of cosmic strings/domain walls?
|
Hello,
I recently found out that walking in front of a building leads to a strange echo (and so does clapping). The noticeable thing is that the facade of the building looks like a flipped staircase (see the rectangle on the image)
If we consider it as a real staircase, the riser ("r") and the tread ("t") do not have ... |
Axions (and more generally, I think scalar fields) can make fundamental constants to vary. Does it include the gravitational constant? And if so, can it be make to oscillate as a simple harmonic oscillator?
|
If a charged pion decays via a charged current $W$, the $W$ boson is much heavier than the pions. How is this not a problem? Could the processes be off-shell in such a drastic manner?
It is tempting consider the $Z$ or $W$ as virtual particles, however if we were to consider the Drell Yan process, weak interaction only... |
How exactly does a bicycle accelerate and decelerate when pedaling and braking?
|
The density of state of a non-relativistic particle ($E = \hbar^2k^2/2m$) in 3D is:
$$\rho_{class}(E) = \dfrac{V}{4\pi^2}\left(\dfrac{2m}{\hbar^2}\right)^{3/2}E^{1/2}.$$
The density of state of an ultra-relativistic particle ($E = \hbar kc$) in 3D is:
$$\rho_{ultra}(E) = \dfrac{V}{2\pi^2\hbar^3 c^3}E^{2}.$$
The density... |
According to MOND, beyond $~a_0~$, the circular orbit speed is derived with $~v = (GMa_0)^{1/4}~$. That gives a constant orbit speed regardless of radius, as in flat rotation curves.
But accelerations vary in the MOND regime, and an object falling towards the center of the field, or on an elliptical orbit, will have a ... |
My question is somewhat related to this post. I wish to know how the infinite dimensional representations are induced from Little group (via action of Boost matrices?). From what I understood was that we have two Casimir Operator
$P^\mu P_{\mu}$
$W^\mu W_{\mu}$
These are used to classify the representation based on m... |
Can one use a CCD in same way as photosensitive paper? When one has very low intensity like in single photons double slit experiment to see the interference pattern one puts a photosensitive paper at the screen and waits as long as it needs even day to see the interference pattern. Does CCD has such mode e.g to read ou... |
In Fano's original paper about Fano resonance [https://doi.org/10.1103/PhysRev.124.1866], starting from equation (3b)
$$V_{E'}a+E'b_{E'}=Eb_{E'}\tag{3b}$$
one gets an expression for $b_{E'}$
$$b_{E'}=\left[\frac{1}{E-E'}+z(E)\delta(E-E')\right]V_{E'}a\tag{4}$$
question (1): where does the second part $z(E)\delta(E-E')$... |
I'm learning about the field theory of electromagnetism. The Lagrangian density for an electromagnetic field can be taken to be
$$
\mathcal{L} = -\frac{1}{4} F^{\mu\nu} F_{\mu\nu} + \mu_0 A^\mu J_\mu
$$
such that the Euler-Lagrange equations reproduce the inhomogeneous Maxwell's equations
\begin{align*}
\partial_\n... |
I would very much appreciate some guidance on the below.
Consider a one-dimensional world as depicted in the attached figure.
We have two (lets say positively charged) particles enclosed by two conductor plates
One plate is at $x=0$ and the other at $x=L$. The particles are at $x_1$ and $x_2$ with respective charges ... |
Once, Hawking has brushed aside the worries about LHC forming black holes massive enough to actually cause damage.
I want to know which estimate he has used. After all, it is not possible to asign a size in the sense of general relativity to a object such as a proton. (Do not come with form factors.)
So quantum gravity... |
I have seen from the graph that Ea is increasing slowly while Fa is increasing really fast. On the other hand Er is increasing faster than Fr. My question is why ? Is there any mathematical idea behind this two plots. Any intuitive idea will be helpful for me.
Extra Details: This is a topic from "Electrical Properties ... |
As I understand the mass of an object doesn't increase in a gravitational field according to general relativity. It just follows a geodesic, its worldline.
Now imagine a small marble falling straight down the gravitational field of a supermassive black hole. And imagine a photon falling down a similar trajectory next t... |
Why is an incidence angle of 45° the best choice in pulsed laser deposition (PLD)?
Why not 20 or 30 degrees, if reflection is effect or not?
|
Entropy for constant temperature process, when instead of volumes, pressures changes from $p_1$ to $p_2$?
|
I am struggling with this problem.
So we're told that any macroscopic state of a gas can be characterized by microscopic stated of a single particle. We divide the microscopic states into groups. So $j$ is the number of groups, $G_j$ is the number of states in the $j$ group and $N_j$ is the number of particles in that ... |
The Gibbs entropy is given by:
$S_G = -k_B \sum P_i log(P_i)$,
where the summation runs over all possible microstates. I've seen one of the assumptions for statistical mechanics was that all microstates are equally likely. But then it seems to me that we would get the Boltzman form for entropy ($S_B = k_B log(\Omega)$)... |
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