Electrical potential Definition and 113 Threads

So I was thinking, I never heard about gravitational potential, yet there is such a big deal about electrical potential. Why is it so much more important that voltage be taught, yet no mention of its gravitational analog?

I have an exam on monday, for a course I'm not familiar with. I have studied the material and tried some example exam question but I can't seem to figure out how to get to the result of the following questions. Q1: Homework Statement A sample of hydrogel is in equilibrium with a sodium chloride...

Hi, I'm trying to understand electrical potential and potential difference. I was wondering if anyone can confirm if what I have written is correct or not? If not I would be glad to learn what I am yet not understanding. When you push away an electron of negative charge from a positive...

Homework Statement Four charges, q1=+q, q2=-q, q3=+q and q4=*q are at the corners of a square with the side a=7.5 cm. (In such way that if one travels along the perimeter of the square, the charge signs are alternating.) If q=3.0 μC, what is the total energy required to assemble this system of...

Hi guys, So my question is related to Electical Potential Eenrgy and Voltage. First off, I am using the Physics book by Cutnell, 8th Edition. If anyone would like to turn to the page I am on, it is page 570 or around there if you have the newer edition. So, they first relate Work by...

Homework Statement Two charges, one of charge +1.5 x 10^–2 C and the other of charge –2.7 x 10^5 C, are 20.0 cm apart. The positive charge is to the left of the negative charge. (a)Draw a diagram showing the point charges and label a point Y that is 5.0 cm away from the positive charge, on...

Homework Statement A sphere with radius 2.0 mm carries a 1.0 μC charge. What is the potential difference, VB - VA, between point B 4.0 m from the center of the sphere and point A 9.0 m from the center of the sphere? (The value of k is 9.0 × 10^9 N∙m2/C2.) Homework Equations The formula...

Hi guys I am learning about electrostatic on my own and was solving some problems but I am having problems with these questions please help. An electron is released within a uniform electric field of a magnitude of 28,000 N/C generated by two parallel plates. The plates are separated by 4 cm...

Yet another quick one I bet one of you will be able to explain in twenty seconds. Going over Electric on my own and I've come across the basics of Potential Difference, when looking at it between points (not in a field) it is defined as electric potentials being different at two points...

Hey physics forums I was kind of curious if there how people measured electric field and of course guass's law before we had computers, so I talked to one of my professors about it. He told me that a long time ago people used something involving plates and soap bubbles to prove that guass's...

Hi all, I apologize in advance if this isn't the right forum to put my question. Homework Statement In our electromagnetism course, we were asked to give the 3D plots of the electric potential V(x/y) for the examples on our book. (We're currently using Introduction to Electrodynamics (3rd...

I have noticed something quite peculiar. If you have equal numbers of e+ and e- charge, there will be more "force pairs" between opposite charges than there are between like charges. Generally speaking, if X is the number of e+ charges and Y is the number of e- charges, then number of "force...

In the case of two charges separarted at a distance r, the electrical potential energy follows that V=(q1q2)/(4*pi*epslion*r), I want to ask why the dimenision of this equation is not consistent and this equation still has a physical meaning. From a textbook about electricity and magnetism, the...

Hi guys, have some problem with Electrical PE. My textbook said sth like this " for the electric field produced by a point charge, we usually choose the energy at infinity to be zero" What does that mean? What is "energy at infinity"? Thx!

I'm currently a Junior in high school and am quite interested in becoming a particle physicist. I have used this site many times before to answer questions, but only when already asked by others. In this case, I finally made an account since I cannot find a good explanation anywhere so here's to...

Homework Statement A potential difference of 24 kV maintains a downward-directed electric field between two horizontal parallel plates separated by 1.8 cm. Find the charge on an oil droplet of mass 2.2 x 10^-13 kg that remains stationary in the field between the plates. Homework Equations...

Homework Statement The questions is as follows: Two isolated infinite parallel conducting sheets are .05 m apart and are initially uncharged. Electrons are then removed from one sheet and placed on the other sheet resulting in a voltage difference of 200V between the sheets. A proton is...

Homework Statement Two point charges Q1 = 3.3 µC and Q2 = 7.6 µC are initially very far apart. They are then brought together, with a final separation of 2.6 m. How much work does it take to bring them together? Homework Equations \DeltaPE = ( k Q1 Q2 ) / r Work = - \DeltaPE k= 8.99 e 9...

A proton is released from rest and accelerates through a potential difference V. The final speed of the proton is proportional to the potential difference in which of the following ways? A. V B. V^1/2 C. V^-1/2 D. V^-1 I think it is V^(1/2) (just√V) but I am no sure exactly how to find...

Homework Statement An axon membrane of a nerve cell is approximately a cylinder of length 12mm and diameter 150micrometres. The membrane has a capacitance of 1.0uFcm^-2. There is a resting potential difference of -90mV between the inside and outside of the cell. How mch electrical potential...

Homework Statement V=(KQ/L)((-ln(d))+(ln(L+d))) is this correct? if not could some one tell me where i went wrong. thanks in advance. there is a part 2 to it as follows: Imagine that distance d is much greater than the length of the rod. Intuitively, the potential should be...

Homework Statement A thin insulating rod is bent into a semicircular wire of radius a, with a total charge of Q distributed uniformly along the rod. Calculate the potential at the center of the curvature if the potential is assumed to be zero at infinity. Homework Equations V=ʃ...

Homework Statement A grey rectangle is a uniform resistive but conducting coating on a substrate. This means that electrons can flow through it, but only slowly, and hence their paths follow the field lines. Attached, and in electrical contact with this, are two silvered metallic conductors...

Homework Statement A Na+ ion moves from inside a cell, where the electric potential is -70 mV, to outside the cell, where the potential is 0 V. Uelec = ? eV Homework Equations I thought you would convert -70 mV to V (therefore it would be -.07) and multiply it by 1.6*10e-19 C. But...

Homework Statement The potential difference between two parallel conducting plates in vacuum is 330 V. An alpha particle with mass of 6.50 x10-27 kg and charge of 3.20 x10-19 C is released from rest near the positive plate. What is the kinetic energy of the alpha particle when it reaches the...

Homework Statement A plutonium-239 nucleus, initially at rest, undergoes alpha decay to produce a uranium-235 nucleus. The uranium-235 nucleus has a mass of 3.90 x 10-25 kg, and moves away from the location of the decay with a speed of 2.62 x 105 m/s. Determine the minimum electric potential...

Homework Statement A +3.00 mirco C charge is separated 4.00cm from a +4.50 mirco C charge. Is the electrical potential zero anywhere? If so, find the location. Explain how the problem changes if the 4.50 mirco C charge is negative. Homework Equations V = E/q V = w/q v = kq/r...

Homework Statement An electron moving parallel to the x-axis has in initial speed of 3.7x10^6m/s at the origin. Its speed is reduced to 1.4x10^5m/s at the point x=2.0 cm. What is the potential difference between the origin and this point? Which point is at the higher potential? Homework...

Alright before I ask the question I'm going to be pretty blunt, I'm not very good at physics at all. I have a great interest and desire to learn physics but it just isn't very easy for me so explanations are going to have to be pretty detailed and even then I still might not get them...

Hello All, I am wondering why the presence of a dielectric reduces the potential difference of a capacitor (after having been separated from its energy supply). I understand how it works, based around maintaining the same charge, I just don't see why. Thank you for the Help.

Homework Statement HELP! A charged particle is stationary between two horizontal charged plates. The plates are 2.0 cm apart. The particle has a mass of 4.0X10^-13 kg and a charge of 2.4 X 10^-18 C. Find the potential difference between the plates. Homework Equations V= EPE/q ...

Homework Statement Is electrical potential energy a vector or scalar? The Attempt at a Solution I think not because electrical potential energy that could be bestowed on one charge by another is determined by the magnitude of the charge and the distance between them and the direction...

Homework Statement What is the electric potential at the point midway between charges of 7.0 microC and 3.0microC which are 3.0 m apart? Homework Equations Va=Va1+-Va2 V= Kq/r The Attempt at a Solution I know how to do the calculations I am just not sure about how to add the...

Homework Statement Compute the electric potential energy for the charge configuration shown below. http://webct6.nic.bc.ca/webct/RelativeResourceManager/Template/CourseMaterials/CourseContent_2007FA/Assignments/PHY060W_Assignment_07_files/image025.jpg Homework Equations...

Homework Statement A positive charge, q1 is at (-20cm,0). An equal and opposite charge q2 is at (20cm, 0). A positive charge q3, equal to q1, is placed at (60cm,0). What is the potential energy of the three charges?? Homework Equations EPE= kq / r The Attempt at a Solution EPE...

Homework Statement Compute the electric potential energy for the charge configuration shown below. http://webct6.nic.bc.ca/webct/RelativeResourceManager/Template/CourseMaterials/CourseContent_2007FA/Assignments/PHY060W_Assignment_07_files/image025.jpg" Homework Equations...

1. Homework Statement Suppose N electron can be placed in either of two configurations. In configuration 1, they are all placed on the circumference of a narrow ring of radius R and uniformly distributed so that the difference between adjacent electron is the same everywhere. In configuration...

Homework Statement Two charged metal spheres are connected by a wire. Sphere A is larger than sphere B. The magnitude of the electrical potential of A... a) is greater than at the surface of sphere B b) is less than at the surface of sphere B c) is the same as that at the surface of...

Is there such a thing in electrical circuits, or anywhere else? Or is this just considered reverse polarity, or 0V?

Hi, I posted this in General but to no avail, any ideas? Hi, Hope I'm in the right place for this question, I am currently studying the basic properties of a plasma and I've come to the understanding that the plasma potential is the potential energy that exists between any two...

Homework Statement This is a qualitative question, so a numerical solution isn't required at any point. It should be easy, I guess, but I'm hanging up at the end. There are three large parallel plates A, B, and C with charges per unit area as follows: A: -8*10^-9C/m^2 B...

hi... if you got resistor, having its positive terminal attached to the positive end of a battery (say emf 5V), and the negative end left connected to a simple wire, as such...in short, the circuit is not complete. what is the pd when a voltmeter is connected across the resistor? is it...

Hello. I'm just stuck on a problem. A point charge Q=+4.60x10^(-9)C is held fixed at the origin. A second point charge q=+1.20x10^(-9)C with mass of 2.80x10^(-4)kg is placed on the x-axis, 0.250m from the origin. The problem asks, "What is the electrical potential energy U of the pair of...

Homework Statement Two protons are aimed directly toward each other by a cyclotron accelerator with speeds of 1350 km/s, measured relative to the earth. Find the maximum electrical force that these protons will exert on each other. Homework Equations Mass of Proton 1.67 * 10 ^{-27}...

Homework Statement Three equal point charges, each with a charge of 2.00 uC, are placed at the corners of an equilateral triangle whose sides have a length of 0.400 m. What is the potential energy of the system? (Take as zero the potential energy of the three charges when they are infinitely...

Hey. I've been told that the total voltage supplied to an electrical series circuit will equal the sum of the potential drop across the circuit. I am a bit confused. Lets say i have a 12V battery in a circuit, so each coulomb of charge obtains 12J of potential energy. What if there are no...

Heres the problem: An infinite nonconducting sheet has a surface charge density of 5.80 pC/m^2. How much work is done by the electric field due to the sheet if a particle of charge q = 1.60x10^-19 C is moved from the sheet to a point P at distance d = 3.56 cm from the sheet? Also if the...

Two particles each have a mass of 5.8E-3 kg. One has a charge of +5.0E-6 C, and the other has a charge of -5.0E-6 C. They are initially held at rest at a distance of 0.70 m apart. Both are then released and accelerate toward each other. How fast is each particle moving when the separation...

Hi, This is probably a dumb question, but I am really having problems understanding just what electrical potential energy/voltage really is. I can apply the formulas in numerical questions, but I just don't understand the concept at all. I totally understand the concept of gravatational...

I am stuck on this problem: I started this problem by looking at the electric potential of a ring, which is: V=\frac{kQ}{\sqrt{R^2+z^2}} So then if it varies in the thickness of the ring, would it be reasonable to have it be: V=\frac{kQ}{\sqrt{(R_{out}-R_{in})^2+z^2}} Or would I...