Electrostatics Definition and 684 Threads

Homework Statement Two Charges +q and -3q are separated by a distance of 1 m. At what point in between the charges on its axis is the potential is zero. Homework Equations I formulated the diagram as given in the attachment The Attempt at a Solution At equilibrium V1 = V2...

An interesting electrostatics puzzle! This is a simplification of a real problem I've been hurting my brain on. Luckily the simplification is a fun challenge in its own right. Homework Statement There is a 3D rectangular solid object in space. Each face of the solid is a perfect...

electrostatics --- calculation of electric field intensity Homework Statement My aim is to calculate electric field intensity at a point P where the test charge qo is kept which is at a distance r from the source charge q is kept. Homework Equations Why it has mentioned limit qo...

Homework Statement Question 2.2 http://www.studyjapan.go.jp/en/toj/pdf/08-007.pdf The picture is in the next page of the problem. k is the Coulomb constant. q+ is the charge at point A. q- is the charge at point B. AC = BC = CD = a Homework Equations E = kq/d² a² = b² + c²...

Homework Statement Consider the transformation: w = i[(1-z)/1+z)] Find the electrostatic potential V in the space enclosed by the half circle x^2 + y^2 = 1, y =>0 and the line y = 0 when V = 0 on the circular boundary and V = 1 on the line segment [-1,1]. Homework Equations w = u +...

Homework Statement I'm trying to work through revisit some basic physics and am working through some electrostatics examples (in Griffith for example). I'm currently working through the 'classic' problem for the http://en.wikipedia.org/wiki/Method_of_image_charges" i.e. a pont charge a...

Homework Statement A negatively charged metallic ball is supported on an insulating stand.We wish to measure the electric field at a point P in the same horizontal level as that of the metallic ball.To do so,we put a positive charge q and measure F/q.The electric field at the point P is...

Homework Statement Ok, so I have a charge inside a conducting sphere. I managed to calculate the electric potential inside the sphere, and also the surface charge distribution, on the interior surface of the sphere. Homework Equations How can I calculate the charge distribution on the...

I was just reviewing some of my concepts of electrostatics, and I am really confused in some things. 1) Why does E equal the negative gradient of V? I understand the definition of the gradient, but in my mind I am just unable to grasp as to why it should be negative only. 2) Why is the work...

Homework Statement Four charges are arranged on the corners of a square whose edge length is a. Two positive charges +Q are placed on diagonally opposite corners, and two negative charges -Q are placed on the other corners. (a) What is the force on a test charge qo placed at the center of the...

1. Three equal positive point charges of magnitude Q = 5.00μ C are located at three corners of a square of edge length d = 7.8 cm. A negative charge -15.00μ C is placed on the fourth corner. At the position of the negative charge, what is the magnitude of the electric field due to the three...

Electrostatics, electrons, protons, and all that good stuff:) Homework Statement Two uncharged metal balls, X and Y, stand on glass rods, are in touch as shown to the right. A third ball Z, carrying a positive charge, is brought near the first two (closer to Y than X). Then the first two...

Homework Statement A solid conducting sphere of radius 'a' having a charge q is surrounded by a concentric conducting sphereical shell of inner radius 2a and outer radius 3a (please refer diagram)... Find the amount of heat produced when switch is closed ... Homework Equations The...

A small demo Van de Graaf Generator can accelerate charges with a potential difference of 3.0 x 10^5 V. How fast can a proton move with the aid of this device? q: charge d: distance V: voltage E: Electrostatic field strength Mass of Proton [According to my formula sheet]: 1.67 x 10^-27 kg...

Hi, again very simple problem Homework Statement Metal sphere of radius R1 is charged to 10V. It is then connected to another sphere with R2 = 2*R1. What is the final potential? Homework Equations The Attempt at a Solution V = E * distance so in the case of disconnected...

Homework Statement The sum of two point charges is 6 micro coulomb. They attract each other with a force of 0.9 Newton, when kept 0.4 m apart in vacuum. calculate the charges. Homework Equations since it is attractive force, i formed the equation q1-q2= 6 *106 and got the relevant...

Homework Statement I am working a problem similar to this problem, (problem 2.18)...

Momentum, Speed, Acceleration 1. Which of these is constant when a charged particle is placed in a uniform electric field? http://img638.imageshack.us/i/lol025.jpg/ 2. If an electron was placed at P, would it accelerate toward D or E? If you can't see, the bottom left charge is +4q and the...

The problem asks an electron is brought to rest by a potential difference of 1kV. what was the initial velocity of the electron? To begin this problem, I first find the change in potential energy by \DeltaU=q\DeltaV. Since electron has a negative charge, I would have a negative \DeltaU. with...

The problem states: how much work is done in moving an electron from a distance of 1nm to a distance of 10nm away from a hydrogen nucleus? My attempt at the problem is using the W=\DeltaU=q\DeltaV. With this equation I would get a positive work. However, when I reason through the question, I...

Homework Statement Why do charged particles come to the surface of a conductor if there is no repulsions between them (the charged particles), as suggested by Columb's Law? Homework Equations Columb's Law F=kq1q2 r2 The Attempt at a Solution The permittivity of...

I am stuck with some misconceptions about electrostatic potential/ potential difference. Please read what follows and correct me wherever I am wrong. Help appreciated. Thanks. :smile: Consider a dipole-like charge configuration (fixed at their positions by unspecified forces ) with the...

ok let's say i that there's two particles with charges Q1 and another with a charge Q2 and they are 5m away from each other. if i wanted to find the location of an electron where it is at rest (or equilibrium) it can be to the left of q1, between q1 and q2, or to the right of q2. heres what...

Homework Statement Imagine a spherically symmetric charge density p(x) = Cr for r≤a and 0 for r>a (a) determine the electric field E(x) and potential V(r). Notice that V(r) and E(x) are continuous at r=a. (b) Now suppose additional charge is placed uniformly on the surface at r=a, with...

Standard electrostatics problem (in spherical polar coords): spherical cavity of radius R in an infinite dielectric of permittivity ε centred at origin of the coord system. Surface charge stuck on to the cavity: \sigma(\theta) = \sigma_0 \cos (\theta) Problem is to find the potential in...

Homework Statement Two point charges, one with charge +q and the other with charge +9q, are placed a distance "d" apart. It is possible to place a third charge so that the net electrostatic force on all three charges is zero. What are the sign, magnitude, and position of this third charge (in...

Homework Statement The z=0 plane has a surface charge density \sigma(x,y) = \sigma0 \cos{(ax+by)} . Find the potential everywhere in space. Homework Equations The Attempt at a Solution Ok, so I tried to just integrate directly: \Phi = \frac{1}{4 \pi \epsilon0} \int_{-\infty}^{\infty}...

Homework Statement This should be simple: We have a charge density in some region of space, r< R (R is some known constant), that goes like 1/r. Everywhere else, the charge density is zero. I need to find the electric field and potential everywhere. The total charge is Q, assumed to be...

Please teach me about this: The tranversal electromagnetic field can be quantized to tranversal photons between two curents.So how to understand at quantum level the electrostatic interaction of classical theory. Thank you very much.

Homework Statement There is a cube with a side length of 0,2m. Its three adjacent walls bear an area charge of -2nC/m2. Find the strength of the electric field at the center of the cube. Homework Equations E = \frac{\sigma}{2 \varepsilon _{0}} dE = \frac{\sigma dS}{4 \pi \varepsilon...

Hello, I am a senior undergraduate majoring in Applied Physics and I plan on starting graduate school for a Master's degree in Electric Power Engineering next year. My question is, how relevant will my Physics knowledge be? So far I've taken an Electronics course where I learned a great...

Homework Statement Two concentric spheres with radius r1=6cm and r2=10cm are charged with electric charges Q1=-1nC and Q2=0.5nC. Find the intensity of the electric field on distance 5cm and 14 cm from the center of the sphere. I think they look something like this Please if anyone...

Hi everyone. I'm in my first semester of Jackson right now, and most of it's fine, but I'm having a hard time understanding the use of Green's functions as Jackson describes them in chapters 1-4. Does anyone know of another good physics reference that might be more clear? I have plenty of...

Homework Statement A ball of mass m with a charge q can rotate in a vertical plane at the end of a string of length l in a uniform electrostatic field whose lines of force are directed upwards. What horizontal velocity must be imparted to the ball in the upper position so that the tension in...

Hi, I'm stuck with a question concerning electric fields : Can an electrostatic potential drop exist in (what I would call) a 0 dimensional system ? Let's imagine we are in a region of space where there is nothing but a uniform magnetic field. So the problem is anisotropic but does not...

Say you have to equal charges q1 and q2 and a distance r between them. We know from electrostatics that the force exerted by one charge on the other is inversely proportional to the square of the distance between them. If you place a massive object at the middle of the segment connecting the...

Homework Statement Determine the amount of work needed to transfer two charges of 40nC and -50nC from infinity to locations (0,0,1) and (2,0,0) respectively. I got an answer but it doesn't seem right Homework Equations Used in attempt The Attempt at a Solution...

Hi, I'm having a bit of a hard time stumbling over the concepts of the following problem: Homework Statement In Electrostatics: How do you modify the div and curl of the electric field from 3D to 2D? What are the 2D and 1D versions of Coulomb's Law? Homework Equations In 3D (sorry, no latex...

[b]1. A proton an an alpha-particle are projected with a velocity v=(Ke^2/mL)^0.5 each, when they are far away from each other. If their initial velocity vectors are anti parallel to each other, with a distance "L" between them, find the distance of closest approach.(mass of proton = m, charge...

I seem to be having trouble grasping a very basic principle in electromagnetism. I have been told, in numerous places, that the electric field inside a conductor is zero. (Electrostatics). Yet I keep coming across problems in the textbook like this one: "Use Gauss's Law to find the electric...

Hello ppl, Four equal charges of +10 m C are placed at four corners of a square. The electric intensity at the center of the square is...? Regards

Homework Statement 1. suppose that your calculator requires .20mA to operate and will be on for 20min while you solve this problem. What quantity of charge will flow during this time? I got 2.4x10^ -2 2. If the potential difference across the nerve of a frog is 85mV and its resistance is...

I was trying to understand the similarities and differences between electrostatics and standard Newtonian mechanics, in particular gravitational formulas. One thing I was curious about is escape velocity. For gravity I've learned that it's sqrt(2GM/R). But for electrostatics, suppose I was...

Homework Statement Two point charges, q1 = -2nC & q2 = +5nC are 4 cm apart. What is the force on q1? What is the force on q2? (Magnitude and Direction) Homework Equations F = kq/r^2 k = 9x10^9 The Attempt at a Solution Using that formula, I calculated q1 to equal -45kN and q2 to...

A positive charged ball hangs from a silk thread. We put a positive test charge q0 at a point and measure F/q0, It can be predicted that E (elect field strength) becomes : a) greater than f/q0 b) equal to f/q0 c) less than F/q0 d) cannot be estimated. Answer (Given) : a) greater than f/q0...

Homework Statement A small spehere with charge of +6.0uc is located near two other small charged spheres. A -3.0uc sphere is located 4.00 cm to the right and a +1.5uc sphere is located 3.00 cm to the left. Determine the resultant electrostatics force on the 6.0uc sphere. Correct answer is...

Homework Statement A thin metallic spherical shell contains a charge Q on it. A point charge q is placed at the centre of the shell and another charge q1 is placed outside it. All the three charges are positive. Find (a) the direction of the force on the charge at the centre, and (b) the...

Homework Statement Charge 0 x 10-9 C is placed on a conducting spherical shell that has an inner radius of 4.8 cm and an outer radius of 6.2 cm. A point charge (-1.9) x 10-9 C is placed inside the shell, at the center. What is the magnitude of the electric field of this configuration, at a...

I was wondering what the different power equations are used for... P=IV, P=I2R, and P=V2/R I was solving for power loss and I noticed that using P=I2R gave me the right answer but the other two gave me different answers