Potential Definition and 1000 Threads

I see that DC power supply have voltage between it's + & - and its 24V. However, there is no voltage with ground. I don't understand - if device's "point" has some potential, why doesn't it give some voltage with ground (which has ~0 potential) I tried this with phoenix contact...

This question is a bit werid because would there be a resulatant electric potential equal to zero as we have a positive and negative charge in which case there's no neutral point. As E1-E2 , they have to be acting in oppostie directions , in this case would they be acting in the same direction.

My question might sound stupid to you but please clear my confusions. I'm taking an circular arc like element on the plate. That arc has a radius of 'r' (AB) and the radius is inclined at an angle 'θ' with OA (∠OAB). The area between arc of radius r and r+dr is dA. dA = 2θr.dr The charge on...

The dipole potential is given by: ##\displaystyle\psi=\int_{V'} \dfrac{\rho}{|\mathbf{r}-\mathbf{r'}|} dV' +\oint_{S'} \dfrac{\sigma}{|\mathbf{r}-\mathbf{r'}|} dS'## I need to prove that ##\psi## is differentiable at points except at boundary ##S'## (where it is discontinuous) I know if...

Hi, I've a question about electricity in the following scenario: consider an accumulator (e.g. a 9V battery) and an analog/digital voltmeter having a probe connected to the accumulator + clamp and the other to the ground (for instance connecting it to a metal rod stuck in the ground). Do you...

Hi all, How to derive the energy of a parabolic confining potential in a wire as shown below? I tried to follow the derivation of the harmonic, oscillator like we did for the quantum well and the magnetic field but i can't find anything that has an expression that come close to the one shown...

In quantum mechanics, I can write the hamiltonian as ##\hat{H} = \hat{p}^{2}/2m + \hat{V}##. I am confusing with the definition of the operator ##\hat{V}##, who represents the potential energy. If the potential energy depend only on the position, is it correct write ##\hat{V} = V(\hat{x})##...

The spring constant of a helical spring is 28 N mñ1. A 0.40 kg mass is suspended from the spring and set into simple harmonic motion of amplitude 60 mm. i use the equation 1/2 change in extension times by force where the force i assume is mass times by 9.8 but the mark scheme uses 1/2 kx ^2 and...

Hello, quick question, when EPE was defined, did we decide that the "test charge" is immobile in the field? Otherwise a force equal and opposite to that of the electric field would just stop the charge from accelerating.

We're given the equation qB=mv/r which is simple enough. I just don't know how to find the velocity given the acceleration through a potential difference. I tried using the radial acceleration equation given to me but I end up with the square root of a negative...and that breaks math... I...

Double integration maybe?? I calculated potential due to shell on plate's center but not on other points on it's surface.

I tried by taking the derivative of the potential to find the critic points and the I took the second derivative to find which of those points are minimum points. I found that the point is ##x=- a##. I don't understand how to calculate the period, since I haven't seen anything about the harmonic...

So I was able to do out the curl in the i and j direction and got 3xz/r5 and 3yz/r5 as expected. However, when I do out the last curl, I do not get 3z2-3r2. I get the following \frac{\partial}{\partial x} \frac{x}{(x^2+y^2+z^2)^\frac{3}{2}} = \frac{-2x^2+y^2+z^2}{(x^2+y^2+z^2)^\frac{5}{2}}...

Hi, My other post got deleted because it was flagged for spam, but it was just a link to a pdf. So I'm uploading the pdf instead. I am working on a model to predict drag on airfoils in 2D potential flow (e.g. vortex panel methods). Currently, XFOIL uses a semi-empirical wake-momentum-thickness...

I understand that the work done is Change of Energy. W = ∫xixf F dx = ΔEThe force is gradient of potential energy F = -∇U (For conservative forces of course) from here, we can say that change of potential energy is W: ΔU = -W but also ΔU = -W = ΔE I'm little bit lost here.. Can you help me...

a) Solution given: F = - x î - y j b) The equilibrium position happens when F = 0. x = 0 and y = 0 is the point of equilibrium. Solution given: (0, 0) c) Since the particle has a circular trajectory the trajectory equation becomes x^2 + y^2 = R^2. The maximum potential energy the...

I want to compute the fraction of time both particles spend outside the finite potential well. All I can get is the probability to find them outside. The wavefunction outside the potential is: $$\frac{d^2\psi}{dr^2} = -L^2 \psi$$ Where: $$L = \sqrt{\frac{2mE}{\hbar^2}}$$ Solving the...

If a solid (a few nm diameter) was placed in vacuum inside a grounded hollow sphere, but without touching the sphere (zero gravity), qualitatively what would the potential inside this solid be on average? In other words I don't want to look so closely that I see the potential wells of the...

I am trying to understand Aubry-Andre model. It has the following form $$H=∑_n c^†_nc_{n+1}+H.C.+V∑_n cos(2πβn)c^†_nc_n$$ This reference (at the 3rd page) says that if ##\beta## is irrational (rational) then the period of potential is quasi-periodic incommensurate (periodic commensurate) with...

Homework Statement [/B] A car battery with a 12v emf and an internal resistance of .040 ohms is being charged with a current of 50A. A.) What is the potential difference across the terminals? B.) The rate of energy dissipation in the battery Pr. C.) the rate of energy conversion to chemical...

By using the equation for the Gravitational Potential -GM/R. It is understand that the max Gravitation Potential would be at infinity point. - G(100M)/22R-(-GM/22R) would be the maximum Gravitational Potential... I guess... Then what would be the next step to find the distance?

Homework Statement The charge of density 3.0 μC/m fills a long cylindrical region having a 2.0-cm radius. If point A is 1.0 cm from the symmetry-axis and point B is 2.0 cm from the symmetry-axis, what is the potential difference VA – VB? a . –25 mV b. +42 mV c. –42 mV d. +25 mV e. +20 mV <-...

Homework Statement The charge of uniform density 50 nC/m3 is distributed throughout the inside of a long nonconducting cylindrical rod (radius = 5.0 cm). Determine the magnitude of the potential difference of point A (2.0 cm from the axis of the rod) and point B (4.0 cm from the axis). a . 2.7...

Homework Statement A charge Q is uniformly distributed along the x-axis from x = a to x = b. If Q = 45 nC, a = –3.0 m, and b = 2.0 m, what is the electric potential (relative to zero at infinity) at the point, x = 8.0 m, on the x axis? a . 71 V b. 60 V c. 49 V <-- correct answer d. 82 V...

Homework Statement Through what potential difference must an electron (starting from rest) be accelerated if it is to achieve a speed of 3.0 x 10^7 m/s? a . 5.8 kV b. 2.6 kV c. 7.1 kV d. 8.6 kV e. 5.1 kV Homework Equations me = 9.11 × 10−31 kg |qe| ≡ e = 1.6 × 10−19 C F = ma Eq = ma V = Eq/r...

<< Mentor Note -- Poster has been reminded to use the Template when starting new schoolwork threads >>[/color] Two particles of identical mass m interact with each other via central potential energy Vcentral(r) = -V0(1-|r|/a), if 0 <= |r| <= a 0, if a < |r| Constants...

Hi all, I have an issue trying to understand the following paragraph from Blundell's book. How, exactly, does the definition of ##\mu_0 = E_F## "make sense"? In the sentence after 30.21, it seems to say that the mean energy for a system with ##N## particles differs from that of a system with...

Homework Statement A particle (mass 6.7 × 10–27 kg, charge 3.2 × 10–19 μC) moves along the positive x-axis with a speed of 4.8 × 105 m/s. It enters a region of uniform electric field parallel to its motion and comes to rest after moving 2.0 m into the field. What is the magnitude of the...

We commonly have E and B defined as: But how can I work in electric field E, instead of vector potential A?

1. Homework Statement the a shell is charged Va=120v shell b is grounded, Vb=0V What is the voltage in the center of shells (vo)? The electric field in the center of shells? The potential energy in the center of shells? Homework Equations Vr=Va+(1/r-1/a)/(1/a-1/b)Vab (from integrals) though I...

Homework Statement [/B] There is a conducting cone with angle α placed so that its vertex is normal to an electrically grounded plate, but electrically insulated from the plate and kept at a constant potential V. Find the potential V and the electric field in the region between the cone and the...

Homework Statement Hello today I am solving a problem where an electron is trapped in a potential well. I have a solved Schrodinger's Equation. I am having problems in figuring out what the wave function should be. When I solved the equation I got a complex exponential. I know I cannot use the...

When I first learned about these subjects, I did what was intuitive to me and treated particles as if they carried potential energy. I would do this similarly for rigid bodies where I would also treat them as a particles with their body's mass at the center of mass. This wasn't helped by...

Homework Statement A conducting sphere has a radius of 2.25 m and carries a positive surplus charge of 35.0 mC. A protective layer of barium titanate is applied to the surface of the sphere to make it safe for laboratory workers nearby. Safety considerations dictate that the potential...

Homework Statement This was in a problem set I found. Suppose that the proton in a hydrogen atom is not a pointlike object, but instead described by a uniform spherical charge distribution with charge e and radius R = 8.7 x 10^-16 m. Using Gauss's law and the definition for the electric...

Homework Statement A satellite with mass of m is circling a star. The radius of the circle is R. At some moment the mass splits to 2 equal masses (the tangential velocity of the masses doesn't change). As a result of the split the kinetic energy in the system is multiplied by k (k>1). What will...

Homework Statement A capacitor consists of two large metal disks placed a distance ##s## apart. The radius of each disk is R ## (R \gg s)## and the thickness of each disk is ##t##. The disk on the left has a net charge of ##+Q## and the disk on the right has a net charge of ##-Q##. Calculate...

Homework Statement Two charges, ##-q_1## and ##q_2## are fixed in the vacuum and separated by a distance ##a##. What should be the velocity ##v## of a particle with mass ##m## and charge ##q##, traveling from an infinitely far point along the line which unites ##q_1## and ##q_2## in order to...

1. Homework Statement Consider a potential field $$V(r)=\begin{cases}\infty, &x\in(-\infty,0]\\\frac{\hslash^2}{m}\Omega\delta(x-a), &x\in(0,\infty)\end{cases}$$ The eigenfunction of the wave function in this field suffices...

Hello everyone, Any object has a gravitational potential energy as a function of the distance from the Earth (R). Does this energy depend only on the rest mass of the object; or one must take into account it's relativistic mass? In other words, if we imagine two identical bullets on the top...

Can someone please explain me the concept of potential energy correctly and in detail.

Homework Statement "A rod of length L lies along the x-axis with its left end at the origin. It has a non-uniform charge density λ=αx where α is a positive constant. a) What are the units of α? b) Calculate the electric potential at A. Homework Equations Linear charge density: λ = Q/L where Q...

Homework Statement I've attached a picture of the circuit below for reference, but the question is asking what the potential is at point D.Homework Equations V = IR[/B]The Attempt at a Solution I was told that the answer was 9V, but I'm a little confused because I thought if I looked at the...

Homework Statement Consider a uniform surface charge density σ on a square of unit area. (a) Compute the electrostatic potential Φ along the line normal to the center of the square. My current attempt at a solution (image attached) is either incomplete or is simply wrong but I am unable to...

Homework Statement We have two semi-infinite coplanar planes defined by z=0, one corresponding to x<0 set at potential zero, and one corresponding to x> set to potential ##V_0##. a) Find the Green function for the potential in this region b) Find the potential ##\Phi(r)## for all points in...

Homework Statement Four charges are arranged at the corners of a square as shown in the figure. Q1 is at (-L/2,L/2), Q2 is at (L/2,L/2), point a is at the origin and Q1=Q2=-Q3=-Q4. Which of the following statements correctly describe the electric field E and the potential at points a,b and c...

Homework Statement Find the electric potential of an infinitely long cylinder shell of radius ##R## whose walls are grounded, when in its interior a line charge, parallel to the cylinder, is placed at ##r=a## (with ##a<R##) and that has a lineal charge density ##\lambda##. Homework Equations...

Chemical potential is defined as the change in energy due to change in the number of particles in a system. Let we have a system which is defined by the following Hamiltonian: $$H = -t \sum_i^L c_i^\dagger c_{i+1} + V\sum_i^L n_i n_{i+1} -\mu \sum_i^L n_i$$ where ##c^\dagger (c)## are creation...

Homework Statement Find electric field at Point A its an arc with uniform density= lamda https://drive.google.com/file/d/14cBqE2dMe_w0nb9LtPG0h1cUOrzGWt6g/view?usp=sharing the problem Homework Equations E=intergal dq/r^2 The Attempt at a Solution I've tried using wolfram and cosine rule to...

Homework Statement An isolated parallel-plate capacitor of area ##A_1## with an air gap of length ##s_1## is charged up to a potential difference ##\Delta V_1## A second parallel-plate capacitor, initially uncharged, has an area ##A_2## and a gap of length ##s_2## filled with plastic whose...