Uniform field Definition and 32 Threads

I would like to discuss the nature of the following effect. At whatever angle and with whatever initial speed the particle fly into a uniform potential field, over time the directions of the instantaneous velocity and field strength converge. The kinematics and dynamics here are trivial, but I...

The correct answer to this problem is: ##\sigma = \varepsilon_0E\frac{\varepsilon-1}{\varepsilon}## Here is my attempt to solve it, please tell me what is my mistake? ##E_{in} = E_{out} - E_{ind}## ##E_{ind} = E_{out} - E_{in}## ##E_{in} = \frac{E_{out}}{\varepsilon}## ##E_{ind} = E_{out} -...

For a uniform field like this, I imagine the two plates that creates it are made of multiple atoms with charges, which are points sources that create radial fields. We know that radial fields don't have parallel fields lines, so how are parallel fields lines form when the field is made of...

Hi, I am interested in designing an electrode that reduces the peak e-field intensity at the edges of the electrode. I've read some papers and it looks like there are quite a few. I'm not really familiar with the terms, so I decided to start off with what looks like is one of the simpler ones...

I have a lot of questions about this single concept. You don't have to answer the questions in the order that I ask, if it is convenient to answer them in a different order. 1. When the dipole moment ##\vec{p}## is in the same direction as the electric field (uniform) it has the least potential...

Hi I have read one excellent explanation on the question I am posting again, at another thread on PF, because I am not able to completely understand the concept. Please spare some more time. I need help to understand how an electric field due to an infinite sheet of charge can be uniform where...

Homework Statement An Ohmic material with some conductivity has a uniform current density J initially. Let's say the current is flowing in the direction of the z-axis. A small insulating sphere with radius R is brought inside the material. Find the potential outside the sphere. Homework...

Can someone explain the math of how potential energy travels from higher potential energy to lower potential energy (PE) along a uniform electric field? I understand that in order for the point charge to move, gaining kinetic energy, it will lose potential energy. But using the equation...

Homework Statement An electron is fired from x = 0 with an unknown V0 at 45 degs to the horizontal between two parallel plates separated by 2 cm. Electric field is 103 j N/C. Find: a) The max value of V0 so that the electrons don’t hit the upper plate 3.75 * 106 m/sHomework Equations If you...

How does look like electric field lines due to change of the uniform magnetic field? Suppose we have a magnetic field between two infunite plates with surface current $i$ which is lineary change with time. Then B-filel is (x - perpendicular to plates, z and y along plates) \begin{equation} B_z =...

Homework Statement While at an engineering internship, you reminisce about the similarities between gravitational fields, electric fields, and magnetic fields. You know that two infinite sheets of opposite charge can be used to create a uniform electric field (for points between the two sheets)...

Problem statement, equations, and work done: A perfectly conducting cube is placed in a uniform electric field in the x direction (see attached). Step1 : Use Gauss's law to determine the electric field inside the cube.##\phi_E = 2E(r)A = \frac{q}{\epsilon_0} →...

Homework Statement An example I am reading has the following setup: a dielectric slab of dielectric constant εr exists between z=0 and z=d, whilst an external electric field E0=E0k is applied with k a unit vector in the z direction. This setup exists for all x and y. The rest of space is a...

If an electron is placed in a uniform electric field it moves from a lower potential to a higher potential.So does it's potential energy decrease.In other words,is PE_{f}-PE_{i}<0? This is confusing me.

Hi, One of the boundary conditions when solving for the potential, \Phi, outside a dielectric sphere placed within a uniform electric field is \lim_{r→0}\Phi(r,θ)<\infty Can anyone explain/prove why this so. Thanks,

Homework Statement An electron is projected with an initial speed v_0 = 1.60 * 10^6 m/s into a uniform field between two parallel plates, separated by a distance of 1cm, and each plate is 2cm across. Assume the field outside the plates is zero. The electron enters the field at a point midway...

Homework Statement the current is i, the circuit is in a uniform magnetic field B normal to the plane of the circuit as indicated Attached is the circuit Homework Equations Get the forces acting on each of their sides. Direction and data module for the following: L = 10cm R = 10cm I =...

Hi, I'm getting some confusing results and can't figure out what is wrong Suppose we have a uniform field E=[0,0,E_z] in a dielectric media. By E=-\nabla\psi we can deduce that \psi(x,y,z)=-z E_z But, taking the Laplacian \nabla^2\psi=\frac{\partial^2 (-zE_z)}{\partial z^2}=0...

A solenoid, of sufficient length to consider external flux to be zero, passes through a uniform magnetic field with significant length on both ends extending beyond the field. Will a torque be exerted upon the solenoid ? Or do the windings effectively mask the internal solenoid field from the...

Homework Statement Electric dipole makes small angle with uniform electric field. Find the frequency of the oscillation using dipole moment p, moment of inertia I, and field magnitude E. Homework Equations Torque=I*(angular acceleration)=I*(theta)'' Torque=p*E*sin(theta) The...

Homework Statement A 10.0 kg box is slid down15.0 m along a 20.0o ramp. The force of friction is 40.0 N. What is the change in the gravitational potential energy of the box? Homework Equations W=Fdcos of theta The Attempt at a Solution W=(40 N)(15 m)(cos 20) =563.8J The actual...

Homework Statement It is estimated that 3.0 x 1010 kg of water flow over Niagara falls each hour. The height of the fall is 65 m. What is the total gravitational potential energy of the water relative to the bottom of the falls that falls in one hour. What is the power represented by the...

Hey, I've recently been studying electric fields, and our teacher told us that the field is approximately uniform between two charged parallel plates, ie the force acting on a unit charge is equal everywhere. This doesn't seem to tie with everything else we've been taught; surely, as you...

Hi, I have a problem working out the answer to one part of a type of uniform field question. My answers to the first three parts of the question are correct, but I'll write out those parts as well because I think it's necessary, to understand the second part: An X-ray tube is operated at 25...

This page contains one derivation for the potential energy: http://www.shef.ac.uk/physics/teaching/phy205/lecture_4.htm" Result: U=-pEcos\theta where E = magnetic field's magnitude P = dipole moment = d*Q d= distance between + and - charge Q= charges' magnitude \theta = angle between the...

Let's say we want to write down the metric in a uniform field. I see two ways of going about this. Method 1: Straightforward arguments using the equivalence principle and photons in elevators show that if a photon with initial energy E rises or falls by dy, then its energy shift is given...

Throughout space there is a uniform electric field in the -y direction of strength E = 540 N/C. There is no gravity. At t = 0, a particle with mass m = 3 g and charge q = -17 µC is at the origin moving with a velocity v0 = 25 m/s at an angle θ = 25° above the x-axis. (a) What is the magnitude...

Imagine two spaceships a distance z apart both moving with the same constant acceleration a. The trailing spaceship shoots a beem of light which will be redshifted by an amount \frac{\Delta \lambda}{\lambda_0} = \frac{az}{c} (assuming that \frac{\Delta v}{c} is very small). Due to the...

Homework Statement An electron has an initial velocity of 2.5 × 106 m/s in the x direction. It enters a uniform electric field ~E = (320 N/C) ˆj which is in the y direction. The charge and mass of an electron are 1.6×10−19 C and 9.11×10−31 kg, respectively. Find the acceleration of the...

Hi. I am new, don't close my thread please My Question is the - sign in front of the equation Delta V = Ed , or Delta V = - Ed, Which one is true? Delta V = Ed , or Delta V = - Ed ?? The Attempt at a Solution

Homework Statement The polarization charge on the surface of a spherical cavity is - \sigma_e cos(\theta) at a point whose radius vector from the centre makes an angle \theta with a given axis Oz. Prove that the field strength at the centre is \frac {\sigma_e}{3 \epsilon_o} parallel to...

I Would like to come up with the capacitance between an infinite sheet and a finite area rectangle as a function of distance. I looked into my old E&M book, it did not consider edge effects I need to include those. Here is the situation. I just spent the day working with a capacitive sensor...