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Suppose a ball of mass $m$ is dropped over a trampoline(consider the young's modulus of the material to be $Y$) from some height $h$. The ball impacts the trampoline, gets slowed down due to the restoring force generated in the trampoline as it curves down, and finally comes to a stop to again begin accelerating in the... |
For example, an accelerated electron will emit EM radiation, but will not emit gravitational radiation.
A common argument used is that the gravitational monopole represents the total mass-energy of a system. As this is conserved, there is no gravitational radiation. Why can’t we use the same argument to say that: the e... |
Problem 1.2 of the E&M text of Purcell & Morin reads:
"Two positive ions and one negative ion are fixed at the vertices of an equilateral triangle. Where can a fourth ion be placed, along the symmetry axis of the setup, so that the force on it will be zero? Is there more than one such place? You will need to solve som... |
Is the resistivity of all (conducting) alloys more than that of all (conducting) metals?
I have read it in some places but then I thought of solder.
|
I am going through lecture notes relating to the parity operator $\mathcal{P}$
My confusion relates to the derivation of the symmetry transformation of the orbital angular momentum
$$\mathcal{P} \vec{L} \mathcal{P}^{\dagger} = \mathcal{P} (\hat{\vec{x}} \times \hat{ \vec{p}})\mathcal{P}^{\dagger} = (\mathcal{P} \hat{\v... |
I can't quite seem to get my head around this although this is what I think is going on:
1) To charge by induction a perspex rod must be charged positively, via contact with a cloth removing negative charge (leaving excess positive charge on rod).
2) Then the positively charged rod is brought near the zinc plate at the... |
How do electrons move in an npn transistor along their energy bands, in active mode?
How does the base current originate in this energy diagram?
|
If you look up galaxies on Wikipedia (at least as of August 14, 2020) you will find a list of classes of galaxies that progresses roughly as follows:
Elliptical galaxies
Shell galaxies
Spiral galaxies
Barred spiral galaxies
Are there any theories for how these form? Is there a known sort of universality that could ex... |
My question is probably basic at first view but I would like to really understand this in details.
The way I understand the role of the phase in quantum mechanics is that as soon as we have a physical quantum state: $|\psi\rangle$, multiplying it by $e^{i \phi}$ doesn't change the physical state. We say that the overal... |
I am reading about the uncertainty principle and its stated that we can not simultaneously determine the position and momentum of a photon. But my question is, if you know the initial momentum of the photon, and assuming that a is very small, than we can say that the central maxima would be very wide. The individual ph... |
First this is only a presumtion. Let say we fire single photons of red light at the double slit to get a interference pattern on the screen. The distances between frindges would have certain quantities. Now, let them mix with intense infrared light which doesn't produce colored frindges. The only intention is to figure... |
I don't really understand what is meant by curved space. Why does mass warp space? Why does curved space alter the velocity of a massive object? Normally to change an object's direction you have to apply some force to overcome inertia. So how does curved space do it? What is space anyway? Layman's terms, please.
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In this thesis, section "1.1.4 Quantum Entanglement", page 19. It is mentioned that "for mixed states, entanglement is necessary but not sufficient to ensure the violation of the Bell inequality". I'm finding it hard to understand the meaning of this statement. What I understand is that only the states that violate the... |
Suppose a man is standing on a merry-go-round which is rotating with some speed, if he jumps out in the radial direction, then the rotation speed of the merry-go-round is unaffected. But I don't understand why should this be so?
I saw this article discussing it, but they don't really explain what's going on, they just ... |
I am reading Polchinski's text book STING THEORY.
In the above of eq.(12.3.8), the differential $D_\theta = \partial_\theta + \theta\partial_z$ is defined and
\begin{equation}
D_\theta = D_\theta\theta'\partial_{\theta'}
+ D_\theta z'\partial_{z'}
+ D_\theta\bar\theta'\partial_{\bar\theta'}
+ D_\theta\bar z'\partial... |
If we use a couple of plates and the casimir force attracts those plates, when the plates are close together, we reduce the surface area of the plates by pushing it downwards and then pull the plates away, there is a net postive energy as Casimir force is constant per unit area. Why doesn't this work?
|
I am working on modeling of a multi-physical system using Lagrange based modeling and we know that Lagrange function, $L$, can be defined as below;
$L= T-V$
where:
$T=$Kinetic Energy
$V=$Potential Energy
Now my query is how to define Kinetic energy and potential energy for a thermal system in terms of $T$ and $V$, so o... |
I couldn't find a stack* forum for pools, so I hope this is the next best place to post.
I have an 18 foot diameter above ground pool in the north west, and I don't like the pool cover that came with it.
I built a deck at the water surface level, about 4' above ground, and now have a concern about someone falling onto ... |
In high school physics, I was taught three different equations related to accelerated motion:
$v=at$
$x=\frac{1}{2}at^2$
$x=vt$
As one does in high school physics, I pretty much just mindlessly used these equations to get an okay-ish passing grade and didn't think about them much. However, I recently noticed that, w... |
I am trying to understand the visualization of the energy gap in the nearly free electron approximation.
Context
The general equation to solve in a periodic potential $V=\sum_G V_G e^{i\mathbf{G} \cdot \mathbf{r}}$ is:
$$\tag{1} \left ( E - \frac{\hbar^2}{2m} |\mathbf{k}-\mathbf{G}|^2\right ) C_{\mathbf{k}-\mathbf{G}}... |
We often discuss mass-density, charge-density, and other such functions: $\rho(x,y)$ for ultra-thin plates and $\rho(x,y,z)$ for 3-d objects. The units for the output of these functions say mass or charge/unit volume like $\frac{kg}{m^3}$ or $\frac{C}{m^3}$. I cannot comprehend a density at a single point.
I suspect th... |
Say we have a car on a rough inclined plane, the maximum constant velocity at which the car can travel is $ V $, the driving force is $ F_d $ and the frictional force is $F$.
Shouldn't the power exerted by the engine be used to:
Overcome the $F$ and $mg\sin\theta$ component of weight.
Cause the car to move at velocity... |
In quantization, one studies maps from functions on the phase space to operators acting on the Hilbert space. Let's fix one such map and call it $Q$.
Deformation quantization is based on the idea that $Q$ can be studied indirectly, by endowing the linear vector space of functions over the phase space with a non-commuta... |
I measured the heat absorbed by water in a microwave, and it was about 80% of the max. power of its specifications.
But when the amount of water decreases too much (100 g or less) the efficiency decreased sharply.
I wonder where the EM energy goes in that case, (or when there is no thermal load inside). It is true that... |
I've been trying to get a physical understanding of these three concepts, and any help would be appreciated. So far this is what I understand:
Dirac semi-metals have relativistic quasi-particles (with or without mass), hence the linear dispersion.
Weyl semi-metals are a special class of Dirac semi-metals with zero ma... |
F(x,y,z) is a uniform vector field defined as <0,0,c>, where c is any constant. S is an area on the x-y plane where its normal vector is defined as <0,0,1>. Moving the vector field source towards the area or moving the area towards the source at constant velocities or at constant accelerations are considered flux chan... |
Indian dishes like the Idli and the Dosa are prepared from a fermented batter composed of mainly rice and black grams. (See here for more information on the preparation.)
Would the fermentation process of the batter result in an increase of its total mass? If so, why?
|
So, based on this question, a molecule containing a radioactive atom will break when the atom decays. But suppose you need a lot energy to break the compound apart --- as in, more energy than the decay of the atom will release (obviously, a molecule this stable isn't actually possible... right?). Will the atom just be ... |
In Wikipedia's article on quantum decoherence, it states that despite decoherence creating the appearance of wavefunction collapse,
A total superposition of the global or universal wavefunction still exists (and remains coherent at the global level), but its ultimate fate remains an interpretational issue.
Most of th... |
I have a question to confirm if my "hunch" is correct. Assuming 2 scenarios of similar force but is exerted at different height of a rectangular object with a pivot point (shown in the pic below). Based on Torque (perpendicular force * distance from the pivot point), it should be easier to tilt the object from F1 loca... |
Young's two-slit experiment is generally credited for demonstrating the wave nature of light. But what about a similar experiment with just one slit? My understanding is that this will create an interference pattern. Shouldn't that be enough to demonstrate light's wave nature? Perhaps the technology available at the ti... |
I am reading the lecture notes given by Professor Leonard Susskind. It's said the horizon appears and gets bigger as the in-falling photon sphere further falls in. Photon sphere here is a falling shell not the one at $R=3MG$.
However, as I can imagine, if the photon sphere presented, the mass is fixed. From Newton's th... |
My first query is why can't we comment about the potential at a particular point why we always define potential difference and secondly why is potential at infinity considered $0$?
|
One of the proofs for time dilation is how pions travel further than they should as their lifetime expands due to their travelling near speed of light.
Now imagine you have 2 pions: one stationary on Earth called A the other accelerated to the near speed of light called B.
We do not need clocks as we do have 2 clocks o... |
The law of Magnetic force is given by:
$$F = q [v , B ]$$
I believe that work cannot be done by this force as displacement dx (which has the direction as v) is always perpendicular to Force.
Is this true for motional EMF?
I have constructed a mechanism for the same. Please rectify it. Constructive criticism is always ... |
Consider the vertical circular motion of a point mass connected to the centre by rigid string. Here the uniform gravity $m\vec{g}$ acts.
I illustrated the situation in the diagram below.
Here if we do a vector addition of $\vec{T}$ and $m\vec{g}$ then we get the centripetal force of a weird direction. It is supposed t... |
As neutrons are neutral an electric field should not attract or repel them. However, as they are composed of a positive and a negative part, called one 'up' and two 'down' quarks, shouldn't those quarks somehow slightly react to that field making the neutron at least a mini electric dipole?
|
Lets's say I make two solar ovens. They each have a set of reflectors angled to direct sunlight into a box topped with glass, and all other sides of the box are covered with insulation that can stand temperatures of ~300o F.
One oven's box is made of cardboard, and the other is metal. Both box interiors are coated with... |
I am very confused now, after reading lot of articles and watching videos on special relativity.
Let's assume there are only two bodies in universe one is moving at 80% of speed of light. Which means from the perspective of still body time for moving body is slowed down. But since we know that motion is relative which ... |
I am studying thermal radiation and considering two radiating black bodies. The book describes the net heat flux as the difference between the flux from object 1 to object 2, and the flux from object 2 to object 1. But if there is a net flux then one object must be hotter than the other. Say object 1 is hotter. Since... |
From the Wikipedia page on internal energy I get the following definition
$$U=TS-PV+\sum\mu_iN_i$$
Hence,
$$dU=TdS+SdT-VdP-PdV+\sum\mu_idN_i$$
For constant pressure and temperature and when there is no transfer of matter,
$$dU=TdS-PdV$$
which is the 1st law of thermodynamics. My question is: For isothermal processes (c... |
I tried to study the relationship between voltage and charge flow through a resistor (Whose rate of change with time indeed gives the current). I figured out that rate of integral of voltage with time should be directly proportional to the net charge flown through the resistor. (So if voltage is a cos wave charge flown... |
Can you please point out the basic flaw in the following reasoning?
I use Minkowski $x^\mu$ and Rindler coordinates $\xi^\mu$
$$ x^\mu = (t,x) $$
$$ \xi^\mu = (\eta, \rho) $$
$$ x^\mu(\xi) = \rho \, (\sinh\eta, \cosh\eta) $$
$$ (x^1)^2 - (x^0)^2) = \rho^2; \qquad \frac{x^0}{x^1} = \tanh\eta $$
$$ ds^2 = -dt^2 + dx^2 = ... |
I was searching for a formula for the magnetic force on a current-carrying conductor, and though I am accustomed to the formula $$F=IlB\sin θ$$ where $I=$ current, $l=$ length of conductor, $B=$ magnetic field strength and $θ$ is the angle between the conductor and the magnetic field lines).
I found another one in the ... |
A comment on a recent question raises an interesting point:
Neutrons can have intrinsic electric dipole moments.
Neutrons also have a nonzero electric polarizability, i.e., they acquire an induced electric dipole moment when placed in an external electric field.
Similarly, electrons can also have an intrinsic electr... |
I am confused about the following passage from my textbook:
When light is incident upon a rough surface, even microscopically rough such as this page, it is reflected in many directions, as shown in Fig. 23-3. This is called diffuse reflection. The law of reflection still holds, however, at each small section of the s... |
Suppose I place a lighter on a wooden table, the lighter has a weight, so it wants to go down, but the table exerts a normal force on it, preventing it from going down trough the table, so the lighter does not move. We can say that this is consistent with Newton's first principle of dynamics, in fact the normal force i... |
Does the resistance of a conductor depend on an inertial frame?
What is the experimental and the theoretical evidences for that?
|
If a ball is lifted against gravity, the work we do is stored as potential energy in it. Simultaneously earth too develops the same amount of potential energy due to the height of which the object is raised. What is the source of energy for earth's potential energy?
|
This question arose when I was told that there were positive and negative lobes in an orbital. I wanted to know on what basis this was proposed and hence I searched it on web and found out that it resembled the phases of the wave. But I always thought of orbital as a 2-d racing circuit for the electron, in which the el... |
It might seem counter-intuitive for gaps to be formed in a "continuous spectrum", but according to Planck energy carried by a photon is quantised and can have only discrete values so therefore accordingly the wavenumber should also be quantised and have only discrete values. Does that mean that when we use an ultra-pow... |
this example by the answer but I don't understand the steps. So please if you understand or have another steps drop it . Thanks
|
The following is taken from Cordes [1] on pulsar astronomy.
The dispersive time delay [is]
$$t_\mathrm{DM}=\frac{e^2}{2\pi m_e c} \frac {\int_0^Dds \text{ } n_e}{\nu^2} = 4.15\text{ms} \text{ DM } \nu_{\text{GHz}}^{-2} \tag{3}$$
where the dispersion measure [and its] standard units (for $D$ in pc, $n_e$ in $\text{cm}^... |
As an example, if communication was done using visible light, communication would be limited by the respective atmospheres, dust and obstacles along the line of sight. At the same time, multiple channels could propagate in parallel, just as we can image the lunar surface from Earth as a plane of pixels instead of solvi... |
A particle has just entered a minuscule (and non-rotating) black hole which is at the end of its life. The black hole is getting smaller really fast as it boils away ejecting tonnes of Hawking radiation. Couldn't the particle come back out of the event horizon as the event horizon gets closer to the singularity? Wouldn... |
So I have seen this exam question where water waves in a ripple tank are being used to demonstrate transverse waves.
The question says:
The frequency of the waves is increased. Describe what happens to the speed and the wavelength of the waves.
The answer to the question is that the speed would stay the same and the... |
How to show that
$\overrightarrow{\textbf{e}}_\sigma\cdot\partial_\mu \overrightarrow{\textbf{e}}_\nu = \overrightarrow{\textbf{e}}_\sigma\cdot\partial^\mu \overrightarrow{\textbf{e}^\nu}$
where $\overrightarrow{\textbf{e}}_\nu$ and $\overrightarrow{\textbf{e}^\nu}$ are the the basis and dual basis vector of some manif... |
If a bar magnet is moved towards a coil, current is induced as there is a flux change.
Consider a circular coil where magnetic field is there only inside the coil covering a concentric area of less than coil's area, implying that the magnetic field inside the coil has no interaction (contact) with coil. If that magneti... |
We know about the general theory of relativity which is modern theory of gravitation. Einstein formed it by stating no action can be observed including gravitational force faster than speed of light. means gravitational force is not instantaneous so it shows if sun eventually disappears hypothetically , we will experie... |
I am self-studying General Relativity with Leonard Susskind's lectures from Stanford. The thing that is bothering me is the notation of GR, specifically, the index notation.
In simple layman terms first, can someone explain these and then move on to the more precise and physics explanation of why:
Why do you need all... |
I am trying to derive the non-abelian Aharonov-Bohm effect by generalising Michael Berry's derivation to the case of non-abelian gauge field $A$.
My derivation so far
We require a degenerate eigenspace in order to achieve a non-abelian Berry phase therefore I take my Hilbert space to be $\mathcal{H} = \mathcal{H}_\text... |
Below is a Dual mass spring system placed on a smooth surface(no friction), let us assume the spring constant as $k$ in this case.
Now if we create a small extension in the spring of value $x_o$, the two masses will perform simple harmonic motion(SHM) individually with amplitudes $A_1$ and $A_2$ respectively such that... |
At this link https://en.wikipedia.org/wiki/Versor#Hyperbolic_versor it is claimed that an hyperbolic versor, defined as:
$$
\exp(a \mathbf{r})=\cosh a+\mathbf{r}\sinh a
$$
where $||\mathbf{r}||=1$ correspond to a Lorentz boost. But I cannot work out a proof. Can anyone help?
I assume one starts by applying the exponen... |
In a manifold with non-zero torsion, how can I show that
$T_{b\hspace{2mm}c}^{\hspace{1mm}a} = - T_{bc}^{\hspace{2mm}a}$
where
$T^b_{\hspace{1mm}ac} \equiv \Gamma^b_{\hspace{1mm}ac} - \Gamma^b_{\hspace{1mm}ca}$
Thank you for any suggestion!
|
Photons are the packets of energy released by continuous oscillation of charges.
But I have some questions about this.
Since the electrons oscillate regularly while transitioning between orbitals then why is the energy released in the form of packets and not continuously in the form of waves ? What causes this discon... |
I am a high school student and my teacher taught me that a cyclist bend while taking a turn on a horizontal road because if he doesn't bend it then it will rotate due to net torque of friction about centre of mass,so he bend the cycle at an angle such that the net torque about COM comes out to be 0,but I want to ask th... |
I was recently watching a fermilab video on loop quantum gravity and at about 4:20 it is stated that, when combined, background independence and diffeomorphism invariance force you to conclude that spacetime is quantized. Why?
|
So in the gym, me and a friend doing 2000 m on the rowing machine burnt the same amount of calories, but I did the exercise in 14 mins and he did it in 10 mins. Given that both of us have similar body types and weigh approximately the same. How is this possible?
I realise that the time difference is only 4 minutes, but... |
During the double slit experiment, when we see interference on the screen that shows the light as a wave, why doesn't it become a particle as soon as it interact with the screen? Wouldn't this be the same as the delayed observation experiment where they put a detector behind the slit and caused the light to become a ... |
I am currently working on a problem to prove the formula for calculating the expected value of an Operator:
$$E(\hat{A})=\int dx dp W(x,p,t)\tilde{A}(x,p)$$
where
$$W(x,p,t)=\frac{1}{2\pi\hbar} \int dy \rho(x+y/2, x-y/2,t) e^{-ipy/\hbar}$$
and
$$\tilde{A}(x,p)=\int dy \langle x+y/2 | \hat{A} |x-y/2\rangle e^{-ipy/\hbar... |
We can define $du$ as $du = đq + đw$.
Can we define the state function of $U$ be $U(q,w)$? Why the state function is defined as $U(T,V)$?
|
How does the diffraction of sound waves differ from the diffraction of EM waves?
EM waves have their electric field vector point in a direction perpendicular to the direction of travel and sound waves do not. But how does this impact diffraction?
|
In gravitoelectromagnetism, an approximation to general relativity in the weak field limit, Einstein's equations simplify into a form very similar to Maxwell's equations. In this field, traditional gravitational fields are referred to as "gravitoelectric" fields, and by changing can induce their equivalent to a magneti... |
The way I (and perhaps most students around the world) was taught QM is very weird. There is no intuitive explanations or understanding. Instead we were given a recipe on how to quantize a classical theory, which is based on the rule of transforming all quantities to operators, and that Poisson bracket is transformed t... |
What mathematical techniques can be used to find the evolution of the temperature of a uniform sphere if it is subject to convective cooling at its surface? Are these techniques different from the case of conductive cooling?
For concreteness, assume the initial, uniform temperature to be $T_0$ and the surrounding tem... |
In the HBO series Chernobyl, they keep dumping sand on top of the reactor and worrying about it melting down into the groundwater. They said they had no way of telling what was happening in the core.
Wouldn't it have been possible to get the state of the core by monitoring neutrinos? The soviets seem to have had reason... |
Background
There are many examples from humans pulling heavy vehicles, ranging from trucks to airliners. When researching the physics behind this, most results pointed to the reduced rolling resistance when the vehicles are on wheels. Because the normal force of the vehicle is multiplied with the rolling coefficient, w... |
This high plank is an example of a 2nd class lever. The fulcrum is at the feet, the load is at the centre of gravity of the body, and the effort is at the hands.
If I know:
My weight (the load force).
The distance from my hands to my feet (the effort distance).
The distance from my centre of my gravity to my feet (th... |
While driving, I noticed the sky had weird rays that appeared converge at some point on the horizon. I took a few pictures in hopes I could figure out what they were. There was a storm coming from the other direction if that's relevant information.
They don't show up quite as well on the pictures, but they were def... |
When try to do bogoliubov transformation on a weak-interaction cold atoms with uniform velocity $\vec{v}$, I used two different approaches, giving two different results.
The Hamiltonian is
$$\hat{H}=\sum_{r}\Psi^{\dagger}(r)\frac{\nabla^{2}}{2m}\Psi(r)+\frac{g}{2}\Psi^{\dagger}(r)\Psi^{\dagger}(r)\Psi(r)\Psi(r)\tag{1}$... |
Let say we are measuring the Hubble parameter (HP) observing two galaxies:one 5 billion light years from us and the second one, 10 billion light years from us. We should get two different numbers of receding velocities depending how much expanding space there is between these objects and us and this ratio is given by H... |
To calculate the effective (screened) coulomb interaction $v_{eff}(q,\omega)$ in an electron gas we basically need sum over all Feynman diagrams which have one interaction line with momentum $q$ and energy $\hbar\omega$ entering them and one interaction line with the same energy and momentum leaving them again.
In the ... |
Let's say we have 2 states of fixed parity $| + \rangle$ and $| - \rangle$ with energies $E_+$ and $E_-$ and we have a P-odd perturbing hamiltonian (on top of the original hamiltonian, $H_0$ whose eigenfunctions are the 2 above), $V_P$. According to 1st order perturbation theory, the corrections to energy for both stat... |
Please consider this thermal radiation problem.
Preliminary/Background: A spherical black body B1, like a star, is in a setting with no other thermally active objects nearby. Space is at a temperature of 0 K. The body has internal reactions (nuclear, say) which cause its surface temperature to be 1000 K when at steady... |
I am given the following conducting track, where on its right side there is a conducting rod with mass $m$ and length $a$ which is free to slide on it. There is a constant magnetic field throughout space $\mathbf{B}=B_0\hat{z}$ where $\hat{z}$ is perpendicular to the frame and goes outwards from the page. At time $t=0... |
I'm in year 10 and I just have a question about resistors. How exactly does a resistor reduce current?
From what I've read the current before a resistor is the same as the current after a resistor so how does the resistor reduce current?
I know that the electrons bump into atoms as they move through a resistor but how ... |
When the source of a sound wave is moving in the direction of the sound wave it is a different scenario than if the receiver of the sound wave is moving in the direction where the sound waves are coming from. Why is this not the case in the relativistic Doppler effect, why is it unimportant whether the source or the re... |
In the typical Maxwell's demon scenario, there is a partition/barrier that the demon opens quickly to let a hot particle diffuse to the other side, thereby decreasing the temperature in one of the partitions and increasing it in the other. Is what is happening in this case that because the temperature has decreased, th... |
I guess there is a sense in which the following is true:
"The Laplacian written on a Riemannian manifold $(M,g)$ can be seen as adding a coordinate dependent mass field to the Laplacian on Euclidean space."
Can someone kindly refer me to a place where this is exactly derived?
(or feel free to write in the derivation... |
Question: We need to find, the angular momentum of the assembly, about the Center of mass.
As per Kleppner and Kolenkow, the general Expression for $\vec{L}$ about any point is:
$$\vec{L_{p}}=I_1\vec\omega_1+I_2\vec\omega_2+I_3\vec\omega_3$$
where $I_1,I_2,I_3$ are moments of inertia about the principal axes. As far a... |
Bell's theorem, together with experiments confirming the ordinary quantum mechanical distant correlation predictions which violate its conclusion for local theories, show that any entirely local theory is incorrect. QFT's microcausality postulate forbids an experiment at one space-time point from influencing the probab... |
Bell's Inequalities are a set of inequalities that establish that theories with "counterfactual definiteness" and "locality" require a set of inequalities (describing the probabilities of making any measurement) to hold. Since quantum mechanics violates these inequalities, it therefore rules out theories with these two... |
In the news report Physicists propose test of quantum gravity using current technology (Lisa Zyga, Phys.org, 27 October 2017), a test is proposed to determine if gravity has a quantum structure. From the report:
With their proposed test, the physicists' goal is to find experimental evidence supporting the idea that sp... |
When people speak of the electric charge of a black hole, do we actually mean it affects things outside of the event-horizon or is it just a property it has?
|
Disclaimer: Before I begin with the question I want to warn that some people would argue that it is a math question and not a physics question. However, it finds it origins in the study of topological order using tensor networks and hence I would argue it counts as mathematical physics.
(If more references/clarificatio... |
For this question there is a table of metals, with their associated work function in eV.
The question was: What is the work function of potassium in eV?
The table given:
Metals | Work function (eV)
Cadmium | 4.07
Caesium | 2.10
Iron | 4.50
Nickel | 5.01
Zinc | 4.30
What I have done so far
I have marked th... |
A classical example of an object attached to a string and revolving horizontally with a constant angular velocity. The object is not rotating around its axis. What happens if we cut the string? Some assumptions: No gravity. Thus, Will maintain the Height. No friction force or any other external force.
The object will t... |
According to the Einstein relationship, the diffusion coefficient $D$ is
$$\lim _{t\rightarrow \infty} \frac{\langle \left(\mathbf{r}(t)-\mathbf{r}(0) \right) ^2\rangle}{6t} = D$$
I have run a MD simulation with $N$ particles, and I have a file which has the location of each particle at every time step.
If I want to ca... |
I am doing a science experiment to see if adding weight to a person affects the time taken for a person to run 20 metres. I am needing to write some background information (1 page) and I am not too sure what I should write about this so I was looking for some help. Thank you!
|
This might seem like a really strange question, but here's my reasoning.
A proton-proton fusion reaction proceeds in two steps:
\begin{align*}
p + p + \text{1.25 MeV} &\rightarrow {}^2_2\mathrm{He} \\
{}^2_2\mathrm{He} &\rightarrow {}^2_1\mathrm{D} + e^+ + \nu_e + \text{1.67 MeV}
\end{align*}
The second step produces o... |
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