Electric potential Definition and 1000 Threads

Homework Statement The image related with this problem is attached. Electric charge is distributed uniformly along a thin rod of length a. with total charge Q. Take the potential to be zero at infinity. Find the potential at the following points (a) point P, a distance x to the right of the...

Homework Statement A charged particle is fixed in place at the origin. A second particle of charge +10^{-6} C is released from rest from very far away (\approx (\infty, 0)). The second particle passes the point (9 m, 0) with a kinetic energy of 1.0 J. Find the electric potential due to...

Homework Statement I previously calculated the electric field for the the arc of the circle and got Ex= Q/2pi^2 e_0 a^2 sin(theta) Ey= Q/2pi^2 e_0 a^2 (1-cos(theta)) I need the electric potential Homework Equations The Attempt at a Solution V=Edr i got an answer interms of theta and since I...

Homework Statement Three charges are at the corners of an equilateral triangle (side L). Determine the potential at the midpoint of each of the sides. Here is the picture...

Homework Statement Homework Equations V = (sigma)/(2*epsilon_0)*((z^2 + R^2)^(1/2) - z) The Attempt at a Solution This was my full equation to find the total electric potential: V = (sigma)/(2*epsilon_0)*((z^2 + R^2)^(1/2) - z) - (sigma)/(2*epsilon_0)*((z^2 + r^2)^(1/2) - z)...

Lets say you have a hollow sphere, which is a conductor, and you put some charge on it. I understand why the electric field inside the sphere is 0, but I don't see why the electric potential V is constant. Could someone explain? Thanks

Homework Statement its not a statement but i was wondering: I'm studying the electric potential and when we have a sphere with inner radious r1 and outer radious r2 that has a charge let's say +Q with a cavity and there is a point charge q inside this cavity so the inner surface will have -q...

Homework Statement Are Electric potential and Electrical Potential Energy same or different? Homework Equations The Attempt at a Solution Electric Potential at a point is defined as the amount of work done in moving a unit positive charge from infinity to that point against the...

Homework Statement An electric dipole consists of 1.0 g spheres charged to +(-) 2.0 nC at the ends of a 10-cm-long massless rod. The dipole rotates on a frictionless pivot at it's center. The dipole is held perpendicular to a uniform electric field with field strength 1000 V/m, then released...

electric potential and fields--capacitors Homework Statement What is the potential difference across each capacitor in the figure? What is the potential difference across each capacitor in the figure? Homework Equations Q=C/V Parallel capacitors: add up series capacitors: (1/c +...

Hi, I've been thinking on this for a while, any help would be great :) I have a box placed over a table. There's a pen kept over the box. What I do here is move the pen slowly, without changing its velocity and bring it down on the table. Assuming the table and box are at a height h1...

Electric Dipole and Electric Potential.. and binomial approximation! Homework Statement An electric dipole at the origin consists of two charges +q and -q spaced distance s apart along the y-axis. a.)Find an expression for the potential V(x,y) at an arbitrary point in the xy-plane...

Homework Statement A 13.0 nC charge is at x= 0 cm and a -1.2 nC charge is at 6 cm. At what point or points on the x-axis is the electric potential zero? Homework Equations V=kq/r The Attempt at a Solution 0=13K/r + 1.2K/(r-0.06) 13(r-0.06)=-1.2r r=5.5 cm There is another...

Homework Statement The hydrogen molecular ion , with one electron and two protons, is the simplest molecule. The equilibrium spacing between the protons is 0.11nm . Suppose the electron is at the midpoint between the protons and moving at 1.5 m/s perpendicular to a line between the protons...

Electric potential... Homework Statement 1000 drops of same size are charged to a potential of 1V each. If they coalesce to form a single drop find its potential... Homework Equations The Attempt at a Solution Here what potential are they talking about?...A drop of liquid will...

Homework Statement \ Hi there! We are currently studying forces and fields in physics and we are in the electrostatics chapter. I am having a bit of trouble fully understanding electric potential energy. The book states that electric potential energy is defined as the work required to move a...

Hi, I was wondering, if a circuit is open, would capacitors still have a potential difference ? If there is no potential difference, can we say its potential is 0 then obtain a charge equal to 0 for the capacitor's charge ?

Homework Statement [PLAIN]http://img203.imageshack.us/img203/5679/physics2h.png Homework Equations Included above I believe... The Attempt at a Solution a) i think dq=\lambda2\pidy Some of the calculus that we are using I am shaky on and I just don't understand what is being asked here...

Homework Statement (a) Calculate the speed of a proton that is accelerated from rest through an electric potential difference of 120V (b) Calculate the speed of an electron that is accelerated from rest through an electric potential difference of 120V The Attempt at a Solution...

Homework Statement I have a series of questions regarding electric potential at various points in space given various point charges. The one that would probably be best to focus on is a charge of +q and a second charge of -2q a distance "d" further along the x-axis, find the non-infinity...

Homework Statement Two point charges, -q and q/3, are situated at the origin and at the point (a,0,0) respectively. At what point on the x-axis does the Electric Field Vanish? Find the potential function and show that the V = 0 equipotential surface is a sphere Homework Equations...

Homework Statement Find an expression for the electric potential a distance z away from the center of a thin uniformly charged rod of length L on a line that bisects the rod. Homework Equations V=k\frac{Q}{r} The Attempt at a Solution Determine the electric potential due to one...

Hello, I'm working on a problem where I'm given V, the electric potential, and asked to find E, the electric field. So I took the partial derivatives and found Ex, Ey, Ez. But now I was wondering how to present this answer, since it is the components of the electric field and not the electric...

Homework Statement Particles A (of mass m and charge Q) and B (of m and charge 5 Q) are released from rest with the distance between them equal to 1.411 m. If Q = 25 µC, what is the kinetic energy of particle B at the instant when the particles are 3.411 m apart? Answer in units of J...

Hey friends, I am stuck up in the derivation of the electric potential energy due to a charge 'Q' at the origin on test charge 'q' at a point p (position vector 'rp'). The derivation is shown below, am just struggling with a minus sign... Electric Potential Energy at P = Work done to move...

Homework Statement The work done by an external force on an electron as it moves from point A to point B is 6.3 × 10-14 J. If it was started from rest and had 3 × 10-14 J of kinetic energy when it reached B, what is the potential difference VB-VA? Homework Equations V = k (q/r) Delta V =...

Homework Statement Determine an expression for the electric potential at a point P a distance z away from the center of a thin uniformly charged rod on the line that bisects the rod. Homework Equations V=k\frac{q}{r}\hat{r} The Attempt at a Solution I've defined r to be the...

In a certain region of space, the electric potential is given by V = y^2 + 5xy - 2xyz. Determine the x-, y-, and z-components of the electric field, E, at (5, 2, 3). Do not enter units. I took the partial derivatives with respect to each coordinate: Ex = -∂V/∂x = -[5y-2yz] = -5y+2yz Ey =...

Homework Statement Two point charges -2Q and +3Q are on the x-axis at the origin and at x = L. Find all the points on the x-axis (not at infinity) where the electric potential is zero. Express your answers in terms of L and Q.Homework Equations V= k*Q/rThe Attempt at a Solution I understand...

Homework Statement Two isolated, concentric, conducting spherical shells have radii R1 = 0.510 m and R2 = 1.10 m, uniform charges q1 = +1.90 μC and q2 = +2.50 μC, and negligible thicknesses. What is the magnitude of the electric field E at radial distance (a)r = 4.50 m, (b)r = 0.840 m, and...

Homework Statement The inner radius of a spherical shell is 13.6 cm, and the outer radius is 15.8 cm. The shell carries a charge of 1.65 × 10-8 C, distributed uniformly though its volume. Sketch, for your own benefit, the graph of the potential for all values of r (the radial distance from the...

Homework Statement Electric Potential from Electric Field Suppose that, as a function of x, y, and z, an electric field has the following components: Ex = 6x^2y, Ey = 2x^3 + 2y and Ez = 0 where E is measured in V/m and the distances are measured in m. Find the electrical potential...

Homework Statement A point charge q = -8 µC is surrounded by two thick, conducting spherical shells of inner and outer radii a1 = 0.3 m, a2 = 0.4 m, a3 = 0.7 m, and a4 = 0.8 m respectively. The inner shell is uncharged; the outer shell has a net charge Q = -10 µC. At this point in the problem...

Homework Statement A particular Gieger counter has a metal cylinder with an inner diameter of 1.9 cm along whose axis is stretched a wire with 24 N of tension. The potential difference between the wire and the cylinder is 870 volts. The wire has a length of 8 cm and an outer diameter of 1.1 X...

I was working on E&M I homework with my friend, and the final question was to find the electric potential at any point on the positive x-axis of a charged disk (where the x-axis is perpendicular to the centre of the disk) We solved this easily enough, starting with a point charge and...

Homework Statement A charge of +21.9 micro-Coulombs is placed at x=-3.3 m, y=0 m, a charge of -8.5 micro-Coulombs is placed at x=0 m, y=+3.8 m, and a charge of +15.6 micro-Coulombs is placed at x=+3.3 m, y=+3.8 m. If a charge of -15.4 micro-Coulombs is placed at origin, what is electrical...

Homework Statement Charges + and -q are placed at -1cm and 1cm along the y axis. If their electric potential energy is -45microJ, what is q? Homework Equations U=qV V=Es The Attempt at a Solution I got an equation for the electric potential between the two charges, but it was...

Homework Statement Much of the material making up Saturn's rings is in the form of tiny dust grains having radii on the order of 10^-6 these grains are located in a region containing a dilute ionized gas, and they pick up excess electrons. As an approximation suppose each grain is sphereical...

Homework Statement How much work is required to assemble eight identical point charges, each of magnitude q, at the corners of a cube of side s? Note: Assume a reference level of potential V = 0 at r = infinity. (Use any variable or symbol stated above along with the following as necessary...

Homework Statement An infinite, uniform line charge with linear charge density λ = +5 µC/m is placed along the symmetry axis (z-axis) of an infinite, thick conducting cylindrical shell of inner radius a = 3 cm and outer radius b = 4 cm. The cylindrical shell has zero net charge. The...

Homework Statement Two positive charges, each with Q = +12 µC, are fixed to the x-axis at x = +a and x = -a, where a = 2 m. Part A was not a poblem to find. (a) Find the electric potential at point A on the y-axis where (xA, yA) = (0, b) and b = 5 m. Take the zero of potential to be at...

Homework Statement A point charge q = -8 μC is surrounded by two thick, conducting spherical shells of inner and outer radii a1 = 0.3 m, a2 = 0.4 m, a3 = 0.7 m, and a4 = 0.8 m respectively. The inner shell is uncharged; the outer shell has a net charge Q = -10 μC. At this point in the...

Homework Statement Two equal point charges Q = 5.18 C are separated by a distance d = 2.00 m. (See figure.) http://homework.phyast.pitt.edu/res/msu/nagytibo/Electromagnetism/Electrostatics/graphics/010a.gif Point A is halfway between the charges and point B is located 1.00 m to the...

Why is the electric potential in the middle of two oppositely charged points 0? Does this also mean that there's no potential energy at this point?

Homework Statement There's no problem per se, I'm just confused by the definition of work and electric potential energy: work done by the electric field is defined to be the negative of delta_U, the change in electric potential energy. This definition makes sense to me. However, according...

Hi, this is my first time posting on the forums, so if I make any mistakes, I'm sorry. Homework Statement This question has already been started here: https://www.physicsforums.com/showthread.php?t=449070 but they never got to part (b). PART A A -10.1 nC point charge and a +18.9 nC...

Homework Statement In the presence of a uniform electric field, E=-6.0 i + .8 j + 3.42 k N/C, assume that the electric potential is -5V at the origin of the coordinate system, and determine the electric potential at the point 2.7 i -2.7 k. Here's what I've done so far \DeltaV=V(2.7, 0...

Homework Statement In the presence of a uniform electric field, E=-6.0 i + .8 j + 3.42 k N/C, assume that the electric potential is -5V at the origin of the coordinate system, and determine the electric potential at the point 2.7 i -2.7 k. Here's what I've done so far \DeltaV=V(2.7, 0...

Homework Statement Consider the following figure. image: http://www.webassign.net/grr/p17-18.gif" (a) Find the electric potential at points a and b for charges of +3.5 nC and -7.6 nC located as shown in the figure. Va= _____ V Vb= _____ V (b) What is the potential difference ΔV...

Homework Statement What electric potential difference is required to accelerate and electron, initially at rest, to the speed at which it will move in a circular path with radius 1cm when the electron enters a region of uniform magnetic field of 1.0T, if the field is perpendicular to the...