What is Potential: Definition and 1000 Discussions
Potential generally refers to a currently unrealized ability. The term is used in a wide variety of fields, from physics to the social sciences to indicate things that are in a state where they are able to change in ways ranging from the simple release of energy by objects to the realization of abilities in people. The philosopher Aristotle incorporated this concept into his theory of potentiality and actuality, a pair of closely connected principles which he used to analyze motion, causality, ethics, and physiology in his aPhysics, Metaphysics, Nicomachean Ethics and De Anima, which is about the human psyche. That which is potential can theoretically be made actual by taking the right action; for example, a boulder on the edge of a cliff has potential to fall that could be actualized by pushing it over the edge. Several languages have a potential mood, a grammatical construction that indicates that something is potential. These include Finnish, Japanese, and Sanskrit.In physics, a potential may refer to the scalar potential or to the vector potential. In either case, it is a field defined in space, from which many important physical properties may be derived. Leading examples are the gravitational potential and the electric potential, from which the motion of gravitating or electrically charged bodies may be obtained. Specific forces have associated potentials, including the Coulomb potential, the van der Waals potential, the Lennard-Jones potential and the Yukawa potential. In electrochemistry there are Galvani potential, Volta potential, electrode potential, and standard electrode potential. In the
thermodynamics, the term potential often refers to thermodynamic potential.
I've been looking at a practice test for an introductory class in quantum physics, and I've found a really weird question. It asks for an estimation of the force that an electron exerts on the walls of a box of known length during a collision.
This seems like an entirely nonsense thing to ask...
Given the potential energy, the force is obtained as F = -∇U(r). A conservative force field F is associated with a potential f by F = ∇f. Does the first expression arise from this last one? If so, with -∇U(r), would one obtain the electric field E instead of the force F?
This question is from Collection of Problems in Classical Mechanics by Kotkin & Serbo, here, the answer is given as the following:
However, the graph of ##-Ax^4## looks like:
so shouldn't the trajectory be just ##x(t)=0##?
Attaching the image of the problem as an image. Somehow text is not copied from the book.
Somehow, I can't imagine the picture in my head. We can do it in 2D plane. I know, it mentions the solution, but need to see the drawing, otherwise, my logic fails.
I thought that maybe, first half space...
I am bit confused with voltage potential terminology again to basics
When it is referred as Voa it is Voltage of "o" wrt "a". Is it correct?
But other major question is
as per the document
I would have written KVL as Voa - I1 * Z = Vn. I am really confused with notation used.
Looking at the image, I see that due to symmetry, the bottom-left negative charge and the bottom-right positive charge cancel out, leaving me with a triangle around the center. I'm not entirely sure how to solve for potential at the origin specifically, but I believe that the potential energy of...
In the given circuit, a transient current will flow and when this current finally stops at equilibrium, the charges ##q_1## and ##q_2## are assumed to deposit at the capacitor plates as shown below. The dashed line indicates an isolated system that will have it's total charge conserved.
If I...
Hey all,
I am looking equations (13.24),(13.25) in Peskin & Schroeder's QFT book and I am confused about how they change from the Callan-Symanzik equation for the Effective Action to the Effective Potential. I thought the relation for constant ##\phi_{cl}## was ##\Gamma[\phi_{cl}] = -(VT)\cdot...
In some cases, photons can be produced in "back to back" (BTB) conditions. For example, electron-positron annihilation produces two photons, each at 0.511 MeV, with equal and opposite momentum. Or pretty close, up to the original velocities of the electron and positron.
Start with a source of...
Problem:
I have done part a) in spherical polar coordinates.
For part b) I thought it would be just:
$$\sigma = -\epsilon_0 \frac{\partial V}{\partial r}$$
But I got confused by "You may want to use different coordinate systems .." So I assume partial derivative w.r.t to r is the spherical...
(a)
I know some of the apparatus needed for the experiment, such as DC power supply, ammeter, voltmeter, maybe rheostat. But I don't know how to change the temperature of diode. What is the correct and safe way to change the temperature of diode?
Thanks
Electric potential = "absolute potential"
Textbooks usually connect both ends of two capacitors, of different voltages, in parallel. What would happen if we only connect one end of the capacitors? Perhaps we would have to solve for Maxwell's coefficients of potential for these two cases (to...
I am struggling with how to go about this; in particular, I'm not sure I understand what state is being alluded to when Ballentine says "For an electron that approaches the surface from the interior, with momentum ##\hbar k## in the positive ##x## direction, calculate the probability that it...
Hello everybody, I consider two electrons that have enough kinetic energy to reach their respective classical electron radius. This would be:
2.0514016772310431402e-13 J
The corresponding speed is v = 287336682 m/s.
The electric field is
E = \frac{k_{e}}{R_e^2} = 1.8133774657059088443 ×...
Here is a depiction of the problem
a) The potential at any point P due to a charge q is given by ##\frac{kq}{r}=\frac{kq}{\lvert \vec{r}_s-\vec{r}_P \rvert}##, where ##r## is the distance from the charge to point P, which is the length of the vector difference between ##\vec{r}_s##, the...
Dear All,
I am trying to calculate the moire potential depth of transition metal dichalcogenide system.
I have attached supporting material obtained from one of the thesis. Here they have describe the continuum model hamiltonian for TMDs homobilayer.
My question is how to obtain the moire...
I got answer for (a), which is 0.51 m
For (b), loss of potential energy = 35 x 9.81 x 0.51 = 175 J
Rate of loss of potential energy = 175 J / 1 s = 175 W
But the answer key is 80 W. Where is my mistake?
Thanks
When a coin is dropped from a certain height and collides with a glass surface, is the majority of the potential energy converted to sound or heat? And how would one determine this as I only hear the sound and cannot measure the significant change in temperature?
It is often argued that Dirac Equation is not valid as relativistic quantum mechanics requires the creation of antiparticles. But, there are also some arguments that suggest otherwise. For example, I saw Arnold Neumaier's website on this that there are multiparticle relativistic quantum...
W_ext is the external work done on B and C, which is 12 J
Delta K_tot is the internal work, which is the work done by A on B plus the work done by A on C
Delta K_tot = 5
Solving for \Delta U, we find that the change in potential energy is 7 J
This answer says otherwise...
I only could calculate the distance travelled by each body, by making the difference between the initial and final electric potential work equal to the work of friction done by the 2 bodies.
I tried to make the kinetic energy of the first electron equal to the electric potential work.
mv^2/2=ke^2/d
We have to solve for the minimum distance between them: d=2ke^2/mv^2=5.05*10^-10 m
The force is: F=ke^2/d^2=9*10^-10 N, which is not correct.
I am given an initial vector potential let's say:
\begin{equation}
\vec{A} = \begin{pmatrix}
g(t,x)\\
0\\
0\\
g(t,x)\\
\end{pmatrix}
\end{equation}
And I would like to know how it will transform under the Lorenz Gauge transformation. I know that the Lorenz Gauge satisfy...
Greetings,
in one of the exercise sheets we were given by our Prof, we were supposed to draw the trajectory of a patricle that moves toward a bounded spherical potential that satisfies
##
V(\vec{r}) = \begin{cases}
V_0 & | \vec{r} | \leq a \\
0 & else \\
\end{cases}
##
for...
For this part(b) of this problem,
The solution is
However, I tried solving (b) like this:
Since ##Q_{total} = 363 \times 10^{-6} C## then ##Q_1 = 181.5 \times 10^{-6} C ## since the equivalent upper capacitor is in series with the equivalent bottom capacitor so should store the same amount...
Hello everyone,
All living things have a growth cycle in which they gain mass and volume.
These elements are obviously and undoubtedly taken from the environment in which these creatures live.
Therefore, it is undeniable that the amount of potassium, for example, in the body increases during...
For 2D charge distribution ρ(x,y)=Ne PDF(x,y), where PDF is the normalized probability density function with its peak on (0,0) and has standard deviations σ x. and σ y. Are the contours with the equal probability "PDF(x,y)=const" the same as the equipotiential contours?, I tend to think that...
Can anyone explain to me why grounded means zero electric potential. I confuse what's the relation between infinite ground conducting plane and its electric potential (the method of images).
I have a several question:
1. Why the conductor plane must be infinite, while in reality there's no...
Can anyone explain to me why grounded means zero electric potential. I confuse what's the relation between infinite ground conducting plane and its electric potential (the method of images).
I have a several question:
1. Why the conductor plane must be infinite, while in reality there's no...
For A.1 of this problem,
The solution is
However, I have a doubt about the linear charge density ##\lambda##.
I don't understand how ##\lambda = \frac {q}{2\pi R} ## since this is not a thin ring, but has a non-negligible width of ##2a##
I think that the toroid has a larger area than thin...
The solution chooses the centre wire to determine the potential difference, where Va−(0.909 A)(2.00 Ω)=Vb and Vb - Va = -1.82
If I choose the top wire (passing through the 12 V battery and 4 Ω resistor), Va - 12 + (1.636 A)(4.00 Ω)=Vb, and Vb - Va is different (= -5.46 V). Why would this path...
I don't understand why the Uranium 238 ions are accelerated
I think ##\Delta V = -2000 V## to accelerate since the ion would be accelerated by more postive charges so ## V_i > V_f ##
For part (a) of this problem,
The solution is
However, my solution is
Am I correct? In the solutions that don't appear to plot the electric potential as units of ## \frac {k_eQ} {a} ## like I have which the problem statement said to do.
Many thanks!
Assume you have a two particle system, A, which has a mass and gravitational pull of g,
and B, an object with low mass,
The system starts at time 0 with the distance between A and B being 0, A being at rest and B having enough kinetic energy to move it a distance r away from A, until time t all...
Hello,
so we have two potitions right, if we take ##\theta = 90## as the first position (i.e. both rods are flat) and then the second position at ##\theta = 0##.
I totally understand the exercise, not difficult. The only issue I am having is the torsional spring... it says that it is uncoiled...
I want to follow the Lienard-Wiechert potential derivation in Robert Wald's E-M book, page 179. I do not understand $$dX(t_\text{ret})/dt$$ on the right side. I assume the chain rule is applied, but I can't see how.
$$ \frac{\partial[x'^i - X^i(t - |\mathbf x - \mathbf x'|/c)]}{\partial x'^j} =...
"Heat is the transfer of kinetic energy between molecules. If the velocity is more, the kinetic energy will be more so that the heat is more."
"As an object's speed increases, the drag force from the fluid increases exponentially. For example, when you drive at high speeds, the frictional force...
when you do a multipole expansion of the vector potential you get a monopole, dipole, quadrupole and so on terms. The monopole term for a current loop is μI/4πr*∫dl’ which goes to 0 as the integral is over a closed loop. I am kinda confused on that as evaulating the integral gives the arc length...
It is to my understanding that if the spring was compressed 10cm, it is due to the Work of the Weight Force of the stone. So:
Work done on the spring by the stone = m.g.x = 7.84 J
The work done on the spring will be stored as potential energy of the spring, so:
Us = W
Us = (1/2).k.x²
k =...
Hi
Unfortunately, I can't get on with the following task.
The system looks like this
it is divided in such a way that the same number of particles is present in each ##\epsilon## section. I am now to determine the energy ##E(P_h,V_h,N)## at the height h using the energy ##h=0## i.e...
1. To find the solution simply integrate the e_r section by dr.
$$\nabla g = A$$
$$g = \int 3r^2sin v dr = r^3sinv + f(v)$$
Then integrate the e_v section similarly:
$$g = \int r^3cosv dv = r^3sinv + f(r)$$
From these we can see that ##g = r^3sinv + C##
But the answer is apparently that there...
I have wrote all feilds and potentials and I want to find the constants.
My first question is " when we say in the a<x<2a the potential is V(x)" then the potential in the a is V(a) or V(0) ( cause it is 0 in our new area) ?
Second one is " when I want to write the gausses law for the point x=a I...
Hello! I am trying to use the wavefunctions of a Morse potential as defined in the link provided. They define a parameter ##z## and the wavefunctions are in terms of z. In my particular case, given their definitions, I have ##\lambda = 132.19377##, ##a=1.318 A^{-1}## and ##R_e = 2.235 A##. I am...