Electrostatics Definition and 663 Threads

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...

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.]

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...

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...

Homework Statement In Fig. 21-42 (I attached an MSPaint rendition of it), two tiny conducting balls of identical mass m and Identical charge q hang from non-conducting threads of length L. Assume \theta is so small that tan \theta can be replaced by its approximate equal, sin \theta. (a)...

I'm currently a high school senior planning on going to college to study Electrical Engineering. I've become quite fascinated by the topic of electrostatics and so I'm wondering what careers/jobs are there in this field?

What is the energy required to bring four identical charges in from infinity such that they occupy the corners of a square with side length r?

please help with this problem...i have No clue how do it Two pith balls of mass m are suspended by silk strings of length L. When they are charged they repel each other at an angle of 2 theta, since like charges repel. Using Coulomb's Law and Newton's Law, derive the following...

Work and Electrostatics - Help! Homework Statement I need to place equal and oppositve charges on a piano and at the top of a 5.0 meter ramp in order to move a 1000 kg box up a 30 degree frictionless ramp. The box has a charge of +Q and the top has a -Q. A) What magnitude charges do I...

Here is the problem, I have no idea how to do this! (In a single straight wire) If the positive charges (density p+) are at rest, and the negative charges (density p-) move at speed v, show that: p- = -(p+)*(gamma)^2

Homework Statement A bohr`s model of an atom,taking the radius of the hydrogen atom as r=5.29*10^-11m ,find the strength of the force on the electron,its centripetal acceleraton and itsorbital speed. Homework Equations The Attempt at a Solution

I was reading my text and doing some problems and I realize that I am having a lot of issues understanding some of the basic stuff :( I have a few questions about charge, fields etc. Like given the charge on an object after charge has been transferred by rubbing, how do you tell how many...

Homework Statement We begin with two capacitors c(1)=6 microFarad and c(2)=3 microFarad in parallel which are connected to V=24Volts. The charged capacitors are disconnected and is being connected to each other on opposite signs (+ to -). How much Energy is got wasted in the process...

EDIT: I'm extremelly sorry, i just noticed the sticky above my post saying not to post homework qustions in the forum. Dear Physics Forums, I am a 16 year old high school student currently doing year 11 physics. To do this weekend we were givin an exercise sheet with various questions...

Homework Statement The problem is a Multiple Choice Question, as follows. Q: An electron moves with a constant velocity in an electric field. What could its direction of motion be? 1> Parallel To Field's Direction 2> Anti-Parallel To Field's Direction 3> Perpendicular To Field's Direction 4>...

Electrostatics test on Tuesday -- helpless Hi all, I have a bit of an awkward problem: it is the end of the year for the 2-year "get your A-levels as an adult"-school I'm currently visiting, and the only test left is in Electrostatics. Unfortunately Physics is a major subject and thus you...

if the capacitor plates are of different sizes and it is connected to battery, will even then the two plates get charges of exactly the same magnitude?

Homework Statement A ping pong ball of mass 3*10^-4 kg is hanging from a light thread 1 m between 2 vertical parallel plates 10 cm apart. When the potential difference across the plate is 420V, the ball comes to equilibrium 1 cm from one side of the original position. What is the tension of...

Hi all, Recently got to thinking about electrostatics and electron densities and band structures. If you have an electrostatically charged piece of material, say for example, a metal, does the density of states of that metal change because of the depletion of electrons? Alternately, if...

Again I am not ssure what to do. An electron(mass 9.11x10^-31kg) is accelerated in a uniform E field (E=3.0x10^4 N/C) between two parallel charged plates. The separation of the plates is 1.6cm. The electron is accelrated from rest near the negative plate and passes through a tiny hole in the...

I had this question on the test yesterday, why does brushing or combing your hair give it "volume"? my answer was because combing or brushing involve collision (like rubbing) between the particles of different object, making one object to become negatively charg and the pther positively...

A particle having mass m and charge q moves along a line under the action of an electric field E = alpha – beta *x where alpha and beta are positive constants and x is the distance from a point where the particle was initially at rest. Then, for an observer moving with acceleration q*alpha/m...