Electrostatics Definition and 684 Threads

in a mass of 12g of carbon there are NA= 6.02215x1023 atoms, each atom has 6 electrons, 6 protons and 6 neutrons. each electron has a charge of -1.6x10-19C and each proton has a charge of 1.6x10-19C, each neutron has no charge. if all the electrons were at the north pole and all the protons at...

at each corner of a rhobus , made of rods, each with a length of B, there are electric charges of "Q" and "q" so that each q charge is opposite a q charge and each Q charge opposite a Q charge. what does the ratio of Q/q need to be so that the angle (alpha) is a)90 degrees b)60 degrees c)45...

Homework Statement three point charges q1,q2&q3 are place at the vertices of triangle as shown in the diagram charge q1 has been given 4.5 X 10^13 extra electrons, charge q2 given 9.0 X10^13 extra electrons and q3 has had 9.0 X 10^13 electrons taken from it. Calculate the electric charge of...

Homework Statement A. Two infinite thin sheets of charge are placed perpendicular to the x axis. The surface charge densities of the two plates are (SC density 1 = 8.5 C/M2) and (SC density 2 = 1.5 C/M2. Placed near plate 2 is a think conducting metal plate with a (SC density of -3.0 C/M) Find...

"In a static situation, the electric field of a conductor can have no component parallel to the surface coz this would violate the condition that the charges on the surface are at rest." would this statement be valid for electric field at the surface of an insulator? Explain your answer...

Am just playing around, and following examples of Fourier transform solutions of the heat equation, tried the same thing for the electrostatics Poisson equation \nabla^2 \phi &= -\rho/\epsilon_0 \\ With Fourier transform pairs \begin{align*} \hat{f}(\mathbf{k}) &= \frac{1}{(\sqrt{2\pi})^3}...

Electrostatics question, need help urgent! Homework Statement A small metal sphere carrying a charge of -2Q is first brought into contact with sphere R Which has a charge of +Q, and then into contact with sphere S which has a charge of +2Q, and finally into contact with sphere T which has a...

Hey. I only just started this unit at school (after coming back from holidays and forgetting everything!) and I'm having trouble with the following problem: Homework Statement "Four point charges A, B, C and D are arranged on the corners of a square of side 25cm. If A and B each have...

Homework Statement Hey guys. So, I got this question in the pic. First of all, I drew what I think to be a one-dimensional lattice (in the green box) but I'm not sure, is it right? Second of all, I don't really understand the question, I mean I know that a potential energy of charge q is...

Homework Statement Hey guys. Is it correct what I did there? Thanks in advance. Homework Equations The Attempt at a Solution

I've "derived" the first Maxwell equation of the divergence of the E-field starting at the Coulomb force of a point charge using Gauss law and even the Dirac delta function to justify the divergence at the origin. Now I'm wondering: when you state the law in differential form, i.e. not...

Can someone please check my answers and explain if I get any wrong? 1. A point charge +Q is inside an uncharged conducting spherical shell that in turn is near several isolated point charges, as shown above. The electric field at point P inside the shell depends on the magnitude of (A) Q...

Homework Statement What are the magnitude and direction of the electric force on the +2.0x10^-6 charge shown in the diagram (included in the attachment)? Homework Equations F = kq1q2/r^2 The Attempt at a Solution I used the Ep = kq1q2/r^2 equation and plugged in the numbers but...

Homework Statement An object with a charge of +4.0 x 10^-18 C and a mass of 1.1 x 10^-15 kg is held stationary by balanced gravitational and electric forces midway between horizontal charged plates. What is the applied voltage V? Homework Equations The Attempt at a Solution I...

Homework Statement A 2.5C charge is moved from a point with a potential of 12V to another point of potential 75V. How much work was done on this charge? Homework Equations ΔV = ΔEp/Q The Attempt at a Solution I am unsure how to do this question but what I did do is I took the two...

"A sphere of homogeneous linear dielectric material is palcced in an otherwise uniform electric field E. Find the electric field inside the sphere." Griffiths uses separation of variables to solve laplace's equation in the interior of the sphere. I have two questions. (1) How can you try...

I bolded the answer I think is correct - I'm just a little unsure on these, any help would be appreciated! 1. A capacitor and resistor are connected in a series with a batter and a switch. The instant after the switch is closed A. the voltage across the resistor is equal to the emf of the...

Homework Statement I didn't know how to display a lot of the symbols, so I wrote the problem out in microsoft word, took a screenshot, uploaded it to photobucket, and linked it. Basically, I have to find the charge density as a function of r given the electrostatic field in the image. Any...

pls help me solve the attached problems.. The comments would be appreciated. Thanks in advance.

Hi, if we only have an electrostatic potential given. How to calculate the charge density? I know of course Maxwell equation, here without any time dependence, but I missed always some further specifications, or I forget something important :confused: :redface: thanks greetings

Homework Statement A square, with each corner as a point charge, A, B, C, and D. They all have the same charge of 5.0 x 10 ^(-6) C. Length of each side of the square is 0.1 m. 2 negative charges diagonal from each other, and the other two are positive, diagonal from each other. Question asks...

(Any number of options may be correct.) Three concentric spherical shells have radii r, 2r and 3r with charges q1, q2 and q3 respectively. Innermost and outermost shells are earthed. Then, (a) q1+q3=-q2 (b) q1=-q2/4 (c) q3/q1=3 (d) q3/q2=-1/3 The answer key tells me that (a), (b)...

THe following is a homework assignment from AP Physics. Homework Statement Two large, flat parallel conducting plates are .10m apart. THe lower plate has a Voltage of 10v while the upper plate has a voltage of 20V. Point P is located .04m from the bottom plate. Find: a) THe magnitude of the...

Hello, I have my first exam tomorrow in Electricity & Magnetism and I really need to know whether I solved this question correct or not, and I do not own the answer key to the book which I took the question from. Thanks in advance! Note: English is not my mother-tongue and neither do I study...

a ball with a mass of 100g is tied to a ceiling on a 1m cord and is charged with a positive charge of 3*10^16 c, what angle will the cord lift to if it is placed next to an infinite board charged with a density of 5*10-6 c/m^2 (positive), the board is placed at a constant angle of 45 degrees to...

Homework Statement The problem is attached as an image. Homework Equations R=integral(rho*D/A) I guess that there is more... The Attempt at a Solution I got stuck stright on A), for I don't have a clue what to do with such a weird Rho value. Afterwords when we want to find E...

the question that i have encountered was: "given an insulated charged sphere, what is the force applied by one half of the sphere on the other half?" i have tried calculating the integral but it seemed a little too complicated for me (plus i am not absolutely confident what the correct...

Homework Statement I have a series of about a dozen questions, my son is taking a course that was outlined by his school " as a great way to get ready for Grade 12" it is mostly multiple choice so if someone could help us choose the right answer with a little bit of an explanation. He has done...

This question is similar to the one that I posted previously: Two point charges each of magnitude 2.09 micro Coulombs, are located on the x-axis. One is at x=1.38 m and the other is at x=-1.38 m. a) Determine the electric potential on the y-axis at y=0.511 m. b) Calculate the electric...

I could really use some help with the following question: Three point charges are located as follows: q1= (0,0) m, q2= (0,-0.120) m, q3= (0.272,0) m. Take q1= 4.37 x 10-9 C, q2= -3.00 x 10-9 C, q3= 6.41 x 10-9 C. a) Find the vector electric field that the q2 and q3 charges together create...

Homework Statement (This isn't a homework problem; I'm just working through Griffiths' "Introduction to Electrodynamics" textbook, and can't find a very clear explanation.) When the relationship between electric field and charge distribution are given by: \nabla \cdot E =...

Homework Statement http://stashbox.org/138351/Image-24.png http://shup.com/Shup/45816/Image-25.png Homework Equations The Attempt at a Solution As you can see, this is an example problem from my text. I'm looking for some clarification in their decision to assume potential...

Homework Statement It is given a hemisperical shell charged uniformally with a density charge equal to s. Calculate the force by which it repels an electric charge q which is put in its center(in the center of the largest diameter).

[SOLVED] Electrostatics Problem I've been trying to solve this problem for the longest time, but it doesn't seem to give enough information. Homework Statement If an alpha particle is fired straight at a nucleus of a gold atom, (q = 79 e) at a velocity of 3.3 x 10^4 m/s, how close will it get...

Homework Statement A charged sphere is suspended by a nonconductive string in a uniform horizontal electric field. The electric field exerts a force on the sphere such that its equilibrium position is diplaced at an angle  = 30° relative to the vertical, as shown in the diagram below. The...

A 2.00 mm diameter conducting sphere in vacuum is charged with +28.0 nC. Determine the potential at a distance of 1.70 m from its center. [Hint: Since 1.70 m >> 2.00 mm this is essentially a point-charge.]

Homework Statement Two identical spheres having the same mass, m = 0.60 kg and the same positive charge, q, are suspended from the same point by strings of length 20.0 cm: (a) What charge q resides on each sphere? (b) The apparatus above is now placed in an upward directed but...

Three Kind of electrostatics problem(quite urgent) Homework Statement The first kind of prbolem is about the dielectric coefficient http://myweb.polyu.edu.hk/~07190086d/phy/q1.zip I know the equations below but I don't know how to relate the E-field into eqn1 The main reason is that I...

So, I believe I've got the math part down but, I'm having trouble understanding the theory. Can someone briefly explain how conductors work? Grounding? Insulators? Direction of electron flow. Induction? Conduction? Anything else would be great, thanks.

electrostatics question! hello all... can anybody helps... If ρv=2sinФ+cosФ(c/m^2) find D?!

[SOLVED] electrostatics, ONE TEENSY little problemo! please HELPPPPP thanks! Homework Statement Two charges of q1 = 1.3 µC and q2 = -2.6 µC are d = 0.60 m apart at two vertices of an equilateral triangle as in Figure P16.56. (d) What is the work required to move a 3.2 µC charge...

Electrostatics Flux Problem Homework Statement A linear charge rho L = 2.0 uC lies on the y-z plane. Find the electric flux passing through the plane extending from 0 to 1.0m in the x direction and from -infinity to infinity in the y direction. Homework Equations Alright, so the formula...

Homework Statement A small conducting sphere of mass M is attached to a string of length L. It is at rest in a uniform electrical field of magnitude E directed due right. The sphere has a charge of Q and the string makes a 30 degree angle with the electric field. a. Calculate the...

Homework Statement a metal grounded sphere of radius R in vacuum has a negative charge inside at a distance a from the centre. a) Draw the e-field in the sphere, b) find the force on the charge, c) and determine the maximal and minimal surface charge density, d) as well as the magnitude of the...

Homework Statement At the neutral point the electric field intensity is zero. Two point charges q1=+2nC and q2=-3nC are separated by 2.0m in air. Where is the neutral point?Homework Equations E=f/q coloumbs law E=E[q1] + E[q2] The Attempt at a Solution i don't have a solution for now since i...

Hi, i have been assigned a series of problems that basically follow the same pattern, but I am unable to solve the first one which is making it difficult to solve the others. here it is An insulated metal sphere (X), that has no net charge (neutral), is brought into contact with a similar...

[SOLVED] simple electrostatics problem Homework Statement a cylinder, the inhomogenous E field is given by E = E_{0} (\frac{r}{R})^{3} the assignment was to calculate Q of a piece of the cylinder of length L in two different ways, by gauss law in integral form and in differential form...

Homework Statement Two point charges (q1=+20 nC and q2=-40 nC) are placed 10.0 cm apart onlong the x-axis. Where can a third charge (q3=+20 nC) be placed so that the net electrostatic force on that charge is zero? Homework Equations F=k(q1q2)/r^2 The Attempt at a Solution It's...

[SOLVED] electrostatics problem Homework Statement Two spherical cavities, of radii a and b, are hollowed out from the interior of a (neutral) conducting sphere of radius R. At the center of each cavity a point charge is placed--call these charges q_a and q_b. Why is it necessarily true...

I'll try my best to describe the question, though Enligsh is not my mother-tounge. Hope I'm clear enough! the problem: There's a thick spherical shell made of insulated material (like a thick ring), with an inner radius a and outer radius b. The shell is charged with a changing charge...