Electric potential Definition and 1000 Threads

HELP!A question on electricity (electric field and electric potential) Homework Statement Three point charges are located at the corners of an equilateral triangle as shown. http://s5.tinypic.com/2hdvalh.jpg a) Find the magnitude and direction of the electric field at P b) Find the magnitude...

Homework Statement A nonconductive sphere has radius R=2.31 cm and uniformly distributed charge q==3.5 fC. Take the electric potential at the sphere's center to be V=0. What is V at the radical distance r=1.45cm and at r=2.31 cm Homework Equations Gauss' Law V=E*ds The Attempt at...

Homework Statement I have two large parallel plates that are conducting and separated by 10.0cm. The charges on the plates are uniform and equal in magnitude but opposite in sign. The difference in potential between the two is 500 V. The first question concerning this is which plate...

Homework Statement Find an expression for the electric potential a distance z away from the center of rod on the line that bisects the rod. Express your answer in term of k, Q, L, z and appropriate constants. Here is the picture. Homework Equations The Attempt at a...

Homework Statement http://img156.imageshack.us/img156/2111/picture2ox5.png Homework Equations N/AThe Attempt at a Solution The correct answer is supposed to be: V1 > V2 > V3 > V4 = V5 = V6 But it is kind of weird... since charge only accumulates at the surface, you would think that...

1. If V= 0 at a point in space, must E=0 there? If E=0 at some point must V=0 at that point? And examples for each? I'm pretty confused on both parts. I haven't really been understanding much of this electric charge/electric field stuff. I know, just from an equation at V= -Ed, but I...

My book first introduces expressions for work and energy by referring to concepts from mechanics and gravitation. It uses the familiar expressions F =mg (-y direction) & U=mgy to explain the expressions it gives for electric potential energy. However... I understand that the force due to gravity...

Homework Statement Imagine a cylinder of radius R and Length L. Both of it's ends are open and it carries a uniform surface charge desnity of sigma (@) Find the electric potential at any point along the axis of the cylinder, and then use that to calculate the electric field at any point...

Homework Statement A ball of outer radius a and inner radius b is charged with charge Q_1 . Inside the ball there is a point charge with charge Q_2 located at radial distance c from the centre of the ball. c<b<a Find the value of the electrostatic potential at the centre of the ball...

Homework Statement Two charges are placed at the corners of a square. One charge, +4.0uC, is fixed to one corner and another, -6.0uC is fixed to the opposite corner. WHat charge would need to be placed at hte intersection of the diagonals of the square in order ot make the potential...

Homework Statement Two identical +9.5e-6C point charges are initially 3.5 cm from each other. If they are released at the same instant from rest, how fast will each be moving when they are very far from each other? Assume they have identical masses of 1.0mg. Homework Equations im not...

Electric potential 3 :) Homework Statement Hey guys. Look at this question, I'm suppose to find how much energy does it take to build this sphere with the new formula. The answer suppose to be (3/5) * (kQ^2/R), instead I got (1/10) * (kQ^2/R). I tried to solve it again and again but...

Homework Statement Hey guys. Look at this question, I already did the first part. I have no idea how to do the second one, even with the clue... Can Someone please help me with that? 10x. Homework Equations The Attempt at a Solution

Homework Statement Hey guys. So I got this question in the pic and also the answer I got. I didn't upload the entire solution because I don't have my scanner until Sunday. I'm not so sure about the solution and I bet some of you have already seen this question and solved it. So my...

Hi there! I have this problem: How to calculate the frequency of the oscillations of an electron from its equilibrium point in this potential: V(z)=k/(2ɛ)*[sqrt(z^2 - 9R^2) - sqrt(z^2 - r^2)]*sgn(z)

Homework Statement To find "E" in an electrostatics problem when you are given the velocities and/or distance, you would use the formula E = Δv/d. Given the information below to start out with, derive the equation E = Δv/d and explain what happens to the negative signs (where do they go and...

all my question is listed in the file below thanks for your help

A plastic rod has been bent into a circle of radius R=8.20cm. It has a charge Q1 = +4.20pC uniformly distributed along one-quarter of its circumference and a charge Q2 = -6Q1 uniformly distributed along the rest of circumference. With V=0 at infinity, what is the electric potential a) at the...

Homework Statement The electric potential in a region of space is , where x and y are in meters. What is the strength of the electric field at (x,y)=(2.1m,2.7m)? The electric force is in V/m. Homework Equations E = -grad(V) E = -dV/ds The Attempt at a Solution I know that i...

Homework Statement http://session.masteringphysics.com/problemAsset/1020825/7/jfk.Figure.21.P56.jpg A proton's speed as it passes point A is 4.40×10^4 m/s. It follows the trajectory shown in the figure. What is the proton's speed at point B? Homework Equations Knowing this would be...

Homework Statement http://img239.imageshack.us/img239/9112/54077471xz4.jpg Homework Equations http://img183.imageshack.us/img183/1450/clipboard01bt7.jpg The Attempt at a Solution The online chapter gave me the above equation for the potential due a continuous charge. I converted pico...

[solved] some basic electric potential questions Homework Statement Find the electric potential established by the nucleus of a hydrogen atom at the mean distance of the circulating electron. Homework Equations V = - Integral of (E (dot) dL) V = kq/r from r distance of a point...

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...

Homework Statement (a) Find the electric potential at a distance of 1.00 cm from a proton. (b) what is the potential difference between two points that are 1.00 cm and 2.00 cm from a proton? Homework Equations I know delta V has to be set equal to something but I am not sure what...

Homework Statement The potential as a function of position in a region is given by V(x) = 3x - 2x^2 - x^3. (x in meters and V in volts). Find equation for electric potential field. Homework Equations v = integral(E * dr) The Attempt at a Solution I tried taking the derivative of...

Homework Statement #1 A -10 nC charge and a +20 nC charge are 15cm apart on the x-axis. What is the electric potential at the spot where electric field = 0? So called the 20nC charge q1 & the -10 nC charge q2. I also defined r1 as distance from the 20nC charge, so r2 must then = .15...

Homework Statement This is from Prob. 2.25 Two point charges with separation d, P is a point at a distance z above the mid-point of the charges. The last sentence asked if one of the positive charges is changed to a negative one, what is the potential at P? What field does it suggest? Explain...

Homework Statement what is the potential 18 cm from a dipole moment 2.6nCm at a) 42 deg to axis b) on the perpendicular bisector note: dipole separation << 18cm Homework Equations electric dipole moment, p = qd where q is charge, d is distance electric potential for point...

Two parallel horizontal plates are 0.4 cm apart in air. An oil droplet of m = 4.9*10^-17 kg is introduced between the plates. If the drop has 2 electronic charges and if there is no air buoyancy, you can hold the droplet motionless between the plates if you keep the potential difference between...

Homework Statement An infinite plane sheet of charge has uniform surface density sigma = 1.00nC. What is the separation between equipotential surfaces differing in potential by 10.0V I just a push in the right direction, thanks

ok, So I am in an entry level physics class (electricity & magnetism) and I am having trouble grasping the idea of voltage/electric potential. Wikipedia describes it as "electric pressure" but that is still pretty foggy. My professor relies heavily on mathematical derivations and barely says a...

Homework Statement A thin plastic rod 15 cm long carries 4.2 nC distributed uniformly over its length. (a) If the rod is bent into a ring, find the potential at its center. (b) If the rod is bent into a semicircle, find the potential at the center (i.e., at the center of the circle of...

Homework Statement Two spheres have a radius of 1cm each and carries 4.3nC and -9nC each. The two sphere are separated by an unknown distance. If both spheres are connected by a thin wire, what wil be the potential on each once equilibrium is reached? and how much charge must move between...

An electron and a proton are initially very far apart (effectively an infinite distance apart). They are then brought together to form a hydrogen atom, in which the electron orbits the proton at an average distance of 5.43 * 10-11 m. What is EPEfinal - EPEinitial, which is the change in the...

Homework Statement In the picture i attached, particles with charges q1 = +7e and q2 = -15e are fixed in place with a separation of d = 23.9 cm. With V = 0 at infinity, what are the finite (a) positive and (b) negative values of x (in cm) at which the net electric potential on the x-axis is...

This isn't really a homework problem. I just want to understand electric potention \DeltaV=Uf-Ui=-W Uf= final Ui=initial Can someone explain to me how electric potential acts between two positive electrons, or two negative electrons or a + and a negative electron. In which cases would...

Hello there! I'm new to the forums. It seems like a lot of very knowledgeable people are here. I have my first question. How can the question below be solved? Thank you for your help.How much work is needed to assemble an atomic nucleus containing three protons (such as Be) if we model it as...

1. Homework Statement Two point charges q and -q are located on the z axis at (x,y,z) = (0,0,a) and (0,0,-a) respectively. Find the potential \phi everywhere 3. The Attempt at a Solution I know all the equations and such, I just don't know how to integrate it. I am guessing that...

Homework Statement Two point charges q and -q are located on the z axis at (x,y,z) = (0,0,a) and (0,0,-a) respectively. Find the potential \phi everwhere The Attempt at a Solution I know all the equations and such, I just don't know how to integrate it. I am guessing that it is...

1000 rain drops, each with a charge of "q" and a potential of "v" fall and make one big drop, losing no charge in the process, what is the potential of the big drop

2 balls are held at a distance of 1m from each other and then released, what will each of their velocities be when they are 2m from one another m1=0.05 (kg) q1=6*10^-6 (c) m2=0.1 (kg) q2=5*10^-6 (c) what i tried was looking at each ball seperately ball1 Energy===>...

Hi everyone, The subject of this topic is what I am looking for. For example if the concentration of a monovalent cation in a solution is 1 mol/L, then how much is the electric potential of this solution? (This solution just contains one kind of monovalent cation and not any anion)...

Hi everyone, I have a uniform electric field in which I place an object. I have read that the electric potential inside my object, \Phi_{in}, and the one on the outside, \Phi_{out} must be equal at the boundary. (ie. \Phi_{in}=\Phi_{out} on the boundary) I don't understand why this is...

there are 2 situations that need explanation. first, the general formula for electric potential as you take potential = 0 at infinity as a reference. Second, the general formula for capacitance on a parallel plate. In situation one, the negative sign does NOT DISAPPEAR, and in the second...

Homework Statement A -3.2 { nC} charge is on the x-axis at x_1 = -9 {cm} and a 14.6 {nC} charge is on the x-axis at x_2 = 16 {cm}. ***At what point or points on the y-axis is the electric potential zero? Homework Equations (1/4*pi*epsilon_0)*[(q1/r2) + (q2/r2)] = 0V The Attempt...

Homework Statement During a particular thunderstorm, the electric potential difference between a cloud and the ground is Vcloud-Vground = 1.3 X 10^8 V, with the cloud being at the higher potential. What is the change in an electron's electric potential energy when the electron moves from the...

I'm back again this week with a problem: A particle has a charge of +1.5 Micro Coulombs and moves from point A to point B, a distance of .20 m. The particle experiences a constant electric force, and its motion is along the line of action of the force. The difference between the particle's...

Homework Statement The drawing (a right triangle) show a uniform electric field that points in the negative y direction (pointing down); the magnitude of the field is 3540 N/C, with a=6.2cm, b=7.7cm, and c=9.9cm. Determine the following electric potential differences. a)Vb-Va between...

Homework Statement Four point charges are individually brought from infinity and placed at the corners of a square whose sides are 0.30 m each. Each charge has the identical value + 4.0 mC. What is the electric potential energy of these four charges? Homework Equations V=kq/r (or...

Homework Statement A proton, initially at rest, is accelerated through an electric potential difference of 500V. What is the speed of the proton? Homework Equations V=k(q/r) Solving for r: r=k(q/v) v=d/t known charge of a proton: 1.6E-19C known value of k: 9E9Nm^2/C2 The...