Charged Definition and 1000 Threads

"If the sizes of charged bodies are very small as compared to the distances between them, we treat them as point charges". Can you explain me the statement. And what does "sizes of charged bodies" refer here. Thanks

How to calculate time until charged particles (Electron/Positron for example) collide starting at velocity= 0 , distance x apart: Using coulombs law, how do I get the velocity and position equation for a pair of unit charged particles? A simple reference link would be great as I know this is...

So first I did the vector stuff. r2-r1= 1.3 i hat-47.5 j hat-14.5 k hat magnitude = 49.68 magnitude squared = 2468.19 Now plugging it all in... F=9E9*6.3E-3*2.8E-3/2468.19=64.322 y vector, -47.5/49.68=-0.956119 j hat Multiply this by force and I get -61.499 but answer should be -36.14

Suppose there is a charged line and near that line, there is a magnetic needle lying in the vertical plane of the line. The magnetic needle is radially placed. If the charged line and the magnetic needle are moving at a same constant velocity(parallel to the line, v<<c) towards an observer. I...

I saw a fascinating video from PBS space time about dissolving an event horizon. See here for reference: The video addresses rotating kerr black holes and charged black holes, but doesn't talk about the combination of rotation and charge. So what happens when you spin up the black hole as...

here is the situation Hi guys, I should illustrate the motion of an electron in both cases, but I cannot really understand how will the field be like in the gap between the two(filled) hemispheres(conductor and non). Another thing is: for the conductive hemispheres, does it make any sense to...

Considering the device above, which uses electric and magnetic fields placed properly to avoid charged moving particles with velocities different from the ratio ##\frac{E}{B}## to exit, getting deflected upwards or downwards. All that is easily demonstrable by equalling the forces acting on the...

From one point of view the charged particle is accelerating and should emit electromagnetic waves. But from the equivalence principle, I think, it should not. Does anybody know the answer?

The Lorentz's force acting on a charged particle perpendicularly "hitting" a magnetic field will be directed upwards, and generally directed towards the center of the circumference traveled by this particle, and so will cause a centripetal acceleration to keep it in a circular motion. By...

Could somebody check my solution in this task? Is it correct?

I have the problem with my solution. I don't know it is correct. Could somebody check it?

My attempt at a solution is shown in attached file "work for #10.png". I used Desmos Scientific online calculator to obtain my final answer.

Electric field for the semi-circle $$E = - \frac {πKλ} {2R} $$ In this case E is equals to 10 N/C Electric field for the straighten wire $$E = 2Kλ * ( 1 - \frac {2y} {\sqrt{4y^2 + L^2}})$$ In this case E is equals to 8 N/C What I'm searching is R, λ, and the length of the wire, so I think...

I took a surface element dA at the surface of square at point x',y' now I took a point on x-axis and calculated the flux. But I got a very complicated integral though it should be simple and I can't interpret it

1)$$\frac{Q}{\Delta V}=\frac{\kappa\epsilon_0A}{\ell}\Leftrightarrow\Delta V=\frac{Q\ell}{\kappa\epsilon_0A}$$$$I=\frac{A\Delta V}{\ell\rho}=\frac{Q}{\kappa\epsilon_0\rho}$$ 2) The charge is decreasing by ##\Delta Q##, so ##Q(t)=Q-\Delta Q##.$$I=\frac{\Delta Q}{\Delta t}\Leftrightarrow\Delta...

I draw the graph like this: For (b), I divided each force vector to e from p1 and p2 as x and y parts. I computed them and got Fx=-4.608*10^(-15)N Fy=-2.52*10^(-15)N However, I am not sure whether I did it correctly or not... I appreciate every help from all of you! Thank you!

Ve=0m/s Vp= 0m/s Qe/Qp= 1.60E-19 Me=9.11E-31 Mp-1.67E-27 Ive pretty much gathered all of the equations I think I need to solve the problem. I just am stuck. The last step I realize that the forces would be equal to each other so I have mp x ap = me x ae but then when I try to solve for the...

qvB=mv^2/R R=mv/qB= p/qB ! As you can see, the difference between this relation and the relation in question is in 'c'. Maybe my way is wrong. Maybe I should get help from relativity because the speed of light is involved here. Please help. Thankful

Well, in this problem, I try to use $$d \tau '= \mu ^2 \sin {\theta} {d\mu} {d\theta} {d\phi}$$ With these domain integration: $$0<\mu<r$$ $$0<\theta<\pi$$ $$0<\phi<2\pi$$ , I get $$V=\frac{1}{4\pi \epsilon_0} \frac{3Qr^2}{2R^3}$$ This result is wrong because doesn't match with Prob 2.21, which...

I found the total work done is: ##\frac{q^2}{8\pi \varepsilon a} + \frac{q^2}{8\pi \varepsilon b} + \epsilon \int E_{1}.E_{2} dv## The third is a little troublesome i think, but i separated into threeregions, inside the "inside" shell, between both shell and outside both. Inside => ##E_{1}.E_{2}...

Hello! how does one produced big ensembles of polarized charged particles (electrons, protons, muons etc.) for certain experiments? In the case of neutral particles (for example the nucleus in an atom) this could be done using a magnetic field, but I guess this won't work that straightforward...

This is the diagram I drew for my calculations: I wanted to see if my work for part (a) makes sense. If there is a variable ##l## that runs along the slant of total length ##L##, a ring around the cone can have an infinitesimal thickness ##dl##. By Coulomb's law, $$\vec{F}=\frac{1}{4\pi...

How does LHC send same-charged particles in opposite directions?

Hello, I need to find the force between the two metal plates, one is charged positively, and another is charged negatively. I have to use surface integration, but then I get two surface integrations because of the two differently charged plates. Now I am confused. Please help me. Thank you in...

Potential depends on the charge contained by the conducting plate. So the plate C should change the electric field and hence potential on both plates A and B. This should change the absolute value of potential,but since A and B are still connected to that cell, I think the potential difference...

From Gauss's Law give ##E=\dfrac{\sigma}{2\epsilon_0}## ##\therefore P_e=\dfrac{\sigma^2}{2\epsilon_0}## Consider at equilibrium (before bubble being charged) ##P_i=P_0+\dfrac{4S}{R}## Using Newton's 2nd Law ##\Sigma F=m\ddot{R}## Let ##R+\delta R## be the new radius Give (after binomial...

First when it is connected to the battery, the capacitors start accumulating charges such that the potential difference equals that of the battery. Then the current stops flowing. ##Q_1 = CV## ##Q_2 = nCV## Where 1 and 2 represent the capacitor with capacitance C and nC respectively Then, when...

The solution to this problem states the electric field is E=σ/ε0. Is that because it's a conducting plate? I know for a non-conducting plate it's E=σ/2ε0. This is a Gauss' Law problem. I know how to derive for non-conducting plate. What's different with conducting plate derivation? Thank you!

I tried considering a little piece of the ring (shaded black below) subtending angle ##d\theta##, and attempted to find the electric field in the vicinity of that piece by a summation of contributions from the rest of the ring: $$dE_x = \frac{dq}{4\pi \epsilon_0 d^2} \cos{\phi} =...

Given the total angles in the x direction, I set up this: (mg/cos(x))*sin(x)-Fe=0 then isolated for x: mgtan(x)=(kq^2)/(2*sin^2x) sin^2(x)*tan(x)=(kq^2)/(2mg) From here I am stuck. How do I go forward when x is contained in two different trig functions on the left?

Can we assume that square charge resembles a sphere shell, and think like electric field at sphere shell's center is 0.

Hi there, tried doing this question but not sure if what I did for part b is right? Appreciate any help! Thanks

I just read an article about how electrostaticly charged filters, such as hvac filters, the charge is reduced if soaked in ipa or washed with soapy water. I know some peoe want to save money so they wash the filters. My question is, why does rubbing alcohol and soapy water cancel the charge...

The movement in the z-direction is easy to solve for, as it's only affected by the gravitational force. However, if there's a magnetic field pointing down along the z-axis, the particle is going to be accelerated along the y-axis (F=q*v *B). The force is always going to be perpendicular to the...

Once I know the Hamiltonian, I know to take the determinant ##\left| \vec H-\lambda \vec I \right| = 0 ## and solve for ##\lambda## which are the eigenvalues/eigenenergies. My problem is, I'm unsure how to formulate the Hamiltonian. Is my potential ##U(r)## my scalar field ##\phi##? I've seen...

Hi I am confused in this question. What Can I do after the steps in second photo?

Can we create at least any one of the following in laboratory? How? 1. A uniformly charged spherical shell of finite thickness 2. A uniformly charged sphere 3. A radially symmetrically charged spherical shell of finite thickness 4. A radially symmetrically charged sphere

In a salt crystal, the distance between adjacent sodium and chloride ions is 2.82×10^−10m. What is the force of attraction between the two singly charged ions?

It seems to me that one can obtain the required result by using just one neutral sphere and one ground wire. Let A be the charged sphere and B be the neutral one. Initially ##Q_A=Q## and ##Q_B=0##. put A and B in contact. As a result ##Q_A=Q/2## and ##Q_B=Q/2##. ground B, so that ##Q_B=0##...

I know that a moving particle is subjected to its own field according to Lienard-Wiechert potentials. But is it possible to write a non-relativistic Lagrangian which, upon variation of the action, give rise to the "correct" equation of motion? If such a Lagrangian/Hamiltonian exists, then is it...

The calculations for the magnetic field produced by a uniformly rotating charged sphere can be found in basically every book on electrodynamics. I wonder what happen with the magnetic fields produced by rotating rigid solid that also present precession and nutation movements. The question comes...

Hello, When a charged particle is inside a magnetic bottle at the right speed, the particle bounces back and forth and is confined inside the magnetic field. The magnetic force does not work on the particle hence the particle's kinetic energy remains constant. That means that the particle may...

I've come to the result (using cylindrical coordinates) #\sigma (z) = (-2q) / (pi*sqrt(R_0*(10R_0-6z)^3) )# and i tried to get #Q# by integrating #2*pi*sqrt(R_0^2-z^2)*\sigma(z)dz# from #-R_0# to #R_0#. But i can't solve that integral. I tried solving it numerically with arbitrary values and it...

This page claims that "[t]he electric field outside the sphere is given by: ##{E} = {{kQ} \over {r^2}}##, just like a point charge". I would like to know the reason we should treat the sphere as a point charge, even if the charges are uniformly distributed throughout the surface of the...

Honestly no idea how to get an answer. I found the electric field between the planes and out of it in those two cases but this didn't take me very far. The final answer is E(B)/E(A)=2. Can someone please explain why?

I tried to do Net force with electric field = E x q minus the gravitational force= mg. However, this gives me a negative net force suggesting the proton is moving downwards. I'm not sure this is correct as the initial velocity was horizontal. Was there no gravitational force before? Am I missing...

If you were to positively contact charge a small ~1 mm diameter sphere using a Van de Graaff generator, and were to charge it sufficiently high enough that field evaporation began to occur, what would happen? Would the rate of evaporation increase exponentially as the field strength would...

If I have a metal electric conducting ball the size of an average snowball (Happy Holidays) and give it a charge of say 0.1 Coulombs and set it on a wooden table, will it ever discharge if not touched by anything else? If so, if it is wrapped in an electrical insulator, will it ever discharge...