Charges Definition and 1000 Threads

An interesting problem posed to me by a friend: A small sphere, initially neutral, of radius ##a## emits ##n## charges ##q## of mass ##m## per unit time isotropically from its surface at a radial velocity of constant norm ##v##. Determine the spatial distribution of charges and currents at...

Homework Statement Two equal charges of magnitude Q each are placed at a distance d apart .Their electrostatic energy is E. A third charge -Q/2 is brought midway between these two charges .The electrostatic energy of the system is now A) -2E B) -E C) 0 D) E Homework Equations EPE = kq1q2/r...

Homework Statement current in wire is in east to west direction.direction of magneetic field below the line Homework Equations right hand thumb rule The Attempt at a Solution i used the right hand thumb rule to find the direction of magnetic field but the magnetic field comes out in in the...

Homework Statement Two spherical point charges each carrying a charge of 40 mC are attached to the two ends of a spring of length 20 cm. If its spring constant is 120 Nm-1, what is the length of the spring when the charges are in equilibrium? Homework Equations 1) F = k*(q^2)/r^2 where k is...

Homework Statement Three point charges each carrying a charge of 11.0 µC are located at the corners of an equilateral triangle of side 15.0 cm. Calculate the magnitude and direction of the force on each charge. Homework Equations k = 9.0x109NM2C-2 F = k⋅(Q1⋅Q2)/r2 The Attempt at a Solution...

Suppose a charge q is placed at point x=0, y=0. A second charge q is placed at point x=8.0m, y=0. What charge must be placed at the point x=4.0m, y=0 in order that the field at the point x=4.0m, y=3.0m be zero?

My professor said that the first two maxwell equation's are about static fields Another fast question: Do a single charge that is moVing generate a magnetic field? I saw a demonstration that explains the magnetic field as an electric field using only special relativity, there is a free charge...

Say, we have two particles of equal and opposite charge in an isolated system in which we neglect gravity. The energy of particle 1 is: E1 = U1 + T1 Where U1 is electrostatic potential energy and T1 is the kinetic energy of particle 1. The energy of particle 2 is: E2 = U2 + T2 Where U2 is...

Hello there, I'm confused on several things such as the potential difference it provides and how it pushes the charges through the wire or conductor or circuit. So when a battery comes into contact with a wire, the positive charges flows from high potential through the circuit to the low...

I can understand force being exerted by an object on another object but I can't understand what all this force between two objects is. Can anyone give the complex and simple explanation, please? I am completely freaking out not being able to understand. Analogies and visualizations are a great...

I am a teacher and I can't work this one out. I am trying to answer (a). I have only included the further parts of the question (b, c and d) so you can see why some parts of the question are included. A single positively charged particle, mass 4.6 x 1027 kg, enters a 4.0 T magnetic field into...

Homework Statement Two charges placed at circumference of a circle of radius ##a## at ##\pi/2## from each other. Find the relative magnitude of third charge kept on the circumference such that the system is at equilibrium.Homework Equations Coulombs law. The Attempt at a Solution Let ##Q##...

refer only to the image above, not the question 4.) Two point charges, Q1 and Q2, are placed 0.30 m apart on the x–axis (shown in the figure above) Charge Q1 has a value of –2.50 x 10–6C. The net electric field at point P is zero. a. What is the sign of charge Q2? ____ Positive ____...

Hello! So this is going into physics because it is a physics problem, but it is maths that is the real problem. So if you came here to help someone with physics and not maths I'm sorry. 1. Homework Statement Find the force of repulsion between two point charges of +1C and +3C if they are...

I came upon this: http://physics.stackexchange.com/questions/174514/will-the-electrostatic-force-between-two-charges-change-if-we-place-a-metal-plat/323006#323006 question on Physics Stackexchange which I found very interesting. The configuration is basically two positive point charges q and...

There are two charges with charge q and mass m and they are in equilibrium. Then, in the diagram why is my teacher saying that electrostatic force(F)=mg? Below is diagram.

Homework Statement Four particles with equal charges q and equal masses m are placed on a plane so that they form the corners of a square with side length a. The charges are then released from rest at this configuration (shown as (i) in the figure). After the release, the particles accelerate...

can someone in detail explain to me why can't a dielectric attract charges?

Homework Statement Two m = 4.0 g point charges on 1.0-m-long threads repel each other after being charged to q = 80 nC , as shown in the figure. What is the angle θ? You can assume that θ is a small angle. Homework Equations Fe=kq2/r2 F=ma Fg=mg The Attempt at a Solution Equation 1:[/B] r =...

Can someone in detail please explain to me why a positive or negative charge can attract to a nuetral object?

I apologize ahead of time if this thread was made in the incorrect post. I have only taken Physics III (Mechanics) and am now taking Physics IV (Electricity/Magnetism). I have yet to find a description of every type of forum here. In class, I was understanding everything that was mentioned and...

Homework Statement A +15 microC point charge Q1 is at a distance of 20 mm from a + 10 microC charge Q2. Fin the resultant electric field at: Ai) the midpoint between the two charges ii) at point P along the line between Q1 and Q2 which is 25 mm from Q1 and 45 mm from Q2. bi) Explain why...

Homework Statement Hi guys, would just too make sure my derivation and insight to why is correct. Question: a) only Homework EquationsThe Attempt at a Solution $$dU=-wd_{ext}$$ $$dU=-F_{ext} \cdot dx$$ Now as the ##F_{ext}## is in the same direction and the direction vector { have not...

Homework Statement We have an electric dipole with moment P=2*[10][/-5] pointing in x direction. What is the force experieced by dipole at origin when a point charge Q=3*[10][/-4] is located at (0.014 m ,0,0) Homework Equations 1. [E][/dipole]=(1/4π[ε][/0])(2p/r3) 2. p=qs 3. F=qE 4. τ=pEsinϑ...

Homework Statement Charge Q is uniformly distributed along a thin, flexible rod of length L. The rod is then bent into the semicircle shown in the figure (Figure 1) . Find an expression for the electric field E⃗ at the center of the semicircle. Hint: A small piece of arc length Δs spans a...

Why does the electric field strength on a straight line (E = k.(Q1/d12+Q2/d22). D1,2 = distance with respect to Q1,Q2) between two point charges vary with the location on this line while the field strength between two parallel plates which remains the same anywhere between the plates...

Homework Statement Charge q1= 8.5 nC is located at the coordinate system origin (0,0), while charge q2= -4.46 nC is located at (a,0), where a= 1.5 m. The point P has coordinates (a,b), where b=0.95 m. A third charge q3= 16.5 nC will b added later. It is a 3 part question, first asking for the...

I understand that a steady flow of current will not induce currents in near by conductors. But, what about a steady flow of current that is being accelerated perpendicularly by a uniform magnetic field? Wouldn't this current produce a time varying magnetic field? This is a conductive disk with...

So I understand that a charged particle moving relative to me has a magnetic field, and does not have one if its stationary relative to me... So is it true that a magnet moving relative to me has a charge? Say I took a bar magnet and threw it away from me way out in space, would it acquire a...

Homework Statement Attached the original script. Sorry but I don't know how to type in latex so its easier to attach photos. Homework Equations ET=Σ6n=1En The Attempt at a Solution I attached what I was able to do, I know there is a mistake is in part (b) that I can't locate and any help or...

Homework Statement A metallic sphere is charged. Where will the charges go? At center or on surface or uniformly distributed. Homework Equations I think it should be uniformly distributed. Cause that's why we have terms like volume charge density like we do q/volume. The Attempt at a Solution...

Homework Statement [/B] Derive expressions for the magnitude and direction of the electric field at point P and the potential at R. Charges Q1 and Q2 are both positive. Distance from Q1 to P is h, distance from Q2 to P is √2 h Homework Equations E = k q/r^2 The Attempt at a Solution I...

Homework Statement hi i was doing a practice physics junior olympiad paper when i got stuck in question 11 in this link [/B] https://www.scribd.com/document/244111815/SJPO-2013-Special-Round-pdf Edit by moderator: Inserted relevant extract of the PDF so that helpers do not have to...

Homework Statement (a) What is the strength of the electric field at the position indicated by the dot? (b) What is the direction of the electric field at the position indicated by the dot? Specify direction as an angle measured ccw from the positive x-axis. ##Q_{1} = 4.0 C## ##Q_{2} = 9.0...

Homework Statement What is the direction of the force F on the -10 nC charge in the figure? Give your answer as an angle measured cw from the +x-axis. Express your answer using two significant figures. Homework Equations ##F = k\frac{Qq}{r^2}## The Attempt at a Solution I started by getting...

Homework Statement Two large parallel metal plates are oriented horizontally and separated by a distance 3d. A grounded conducting wire joins them, and initially each plate carries no charge. Now a third identical plate carrying charge Q is inserted between the two plates, parallel to them and...

Homework Statement Written Problem: Summing the Electric Field Three point charges q1, q2, and q3 are placed along a straight vertical line to create a “tripole”. At point P, which is directly to the right of q1, the net electric field is exactly zero. We also know that q1 = 1 μC. b) Write a...

Homework Statement Two point charges are placed on the x axis. The first charge, q1 = 8.00 nC , is placed a distance 16.0 m from the origin along the positive x axis; the second charge, q2 = 6.00 nC , is placed a distance 9.00 m from the origin along the negative x axis. Photo shown by...

Is electricity really the motion of electrons or charges? I'm kind of confused about the distinct differences. Any extra information would be greatly appreciated. I'd love to learn as much detail about this stuff as I can! Thank you!

I ask this because of this diagram. Say that two charges are held a certain distance apart and are let go. Well, we see that the field lines of one charge repels the other. And I noticed that the field lines for an accelerating charge also bends. So can we say that because one field...

Homework Statement Hi, everyone. I have a square and on each vertex of the square is a point charge of "+q". The square has a side length of "r" and these four charges form a system. My problem says to find the work required to assemble the charges shown above, bringing each charge in from...

When a charge placed at anywhere,then it produces a powerful field around itself,is called electric field. It is exist whenever charge exist.And charge takes very very small time in propagate electric field.

Homework Statement What is the electric potential at P due to charges Q1 and Q2...

If you bring a positive charge near a thin conducting sheet, it will induce a negative charge on the side nearest to the charge. And in order for the conducting sheet to remain electrically neutral, a positive charge of equal magnitude will be induced on the other side. How could the conductor...

How to find some papers on Lorentz invariant extensioning of standard electromagnetism that include magnetic charges

Homework Statement Is a current that produces a magnetic field always going to be either an electron or a proton?

Homework Statement A ball of mass m is attached to a rope of length L which has one end at the origin; the ball moves in a horizontal circle at constant speed v0 on a frictionless plane; the velocity is always at 90◦ to the rope. The ball has a charge q, and moves in a constant magnetic field...

Homework Statement In an experiment modeling point charges I had to find equipotential lines. I did so using a voltmeter. The results looked like this: Not a good quality picture, but the equipotential line on the right says 1.3 mV and the one on the left says 2.3mV. From this I had to...

In QCD, quark is in fundamental representation of SU(3) and thus it has to have 3 charges (what we came to call "colors"). Gauge bosons are in adjoint representation and there are 8 of them. The choice how to assign color charges to them is not unique, one popular choice is based on Gell-Mann...

Homework Statement I have two related questions here. 1. A positive point charge is moving directly toward P. The magnetic field that the point charge produces at P is? 2. Two positive point charges move side by side in the same direction with the same velocity. What is the direction of the...