# Tagged Questions

1answer
16 views

### Want to achieve maximum magnetic force & find out the max point [closed]

Hi Sir/ Madam Want to achieve maximum magnetic force & find out the max point for this setting, want to know is the strongest magnetic force must in the 'dot' area ( middle poin of setting ) ...
0answers
43 views

### Materials in Electrostatics [closed]

A point charge $q$ is placed at the centre of a sphere of linear dielectric material of permittivity ε. The sphere is of radius $a$ and is placed in a vacuum. How would I go about finding the ...
1answer
95 views

### Are dc and ac currents produce electric field?

I have four different situation and i want to learn what kind of field (electric or magnetic) each produces and which produces electomagnetic waves? 1)dc current flow in a conductor 2)ac current ...
0answers
118 views

### Electric fields between 2 spheres with different voltages [closed]

Consider two spheres, both with the same diameter. Case 1: sphere A is 100v, sphere B is 0v Case 2: sphere A is 50v, sphere B is -50v Which case has the higher electric field? Electric potential ...
0answers
121 views

### Calculating Electric Field from a Potential Difference w/o Charge

So here is my homework question: Two long cylindrical shells of metal (radii $r_1$ and $r_2$, $r_2 > r_1$) are arranged coaxially. The plates are maintained at the potential difference ...
1answer
45 views

### Need a more efficient way to find where the $E$ field is zero

So this is a problem I already know how to solve, but I feel like my method is really inefficient and I'm wondering if there's a more intuitive, less tedious way to arrive at this conclusion. If we ...
2answers
291 views

### Calculate electric potential and electric field of uniformly charged wire

Say you have a uniformly charged straight wire of length $2L$ going from $-L$ to $+L$ along the $z$ axis with its midpoint located at $z=0$. What is the electrostatic potential, in cylindrical ...
0answers
73 views

### insulator based gauss law questions

My book is incredibly scarce on insulator based Gauss law questions. Conductors seem to handle themselves pretty simply. Here's a question I'm working on that isn't part of my book. where the radii ...
1answer
245 views

### Electric field outside a sphere with a cavity

I have a sphere of radius $2a$ centered at the origin and made of a nonconducting material that has a uniform volume charge density $\rho$. A spherical cavity of radius $a$ eccentric to the right side ...
1answer
88 views

0answers
182 views

### The electric field inside a uniformly polarized cylinder

Given a uniformly polarized cylinder with some polarization $P\vec{z}$ which has radius $R \gg d$ where $d$ is the height and $R$ is the radius. The cylinder's center is on $\vec{z}$ and it's on the ...
3answers
214 views

### Horizontal $E$-field for a charged conducting disk

For part of a simulation I am writing, I need to know the electric field emitted from a charged conducting disk. If the disk was laid out in the $x$-$y$ plane, I am interested in the field in that ...
1answer
93 views

### Maximum separation when 2 unlike charges shot apart

I want to compute the maximum separation when 2 unlike charges are shot apart from each other ...
1answer
331 views

### Electric field around charged cylinder

This is a homework question, so please don't give me the answer outright. I just need help conceptually. "A cylindrical shell of length 190 m and radius 4 cm carries a uniform surface charge density ...
0answers
71 views

### Static electrical attraction [closed]

Coulomb's law is used to calculate the electrical attraction between 2 charged particles, what formula do I use to calculate an electrical attraction magnitude between 2 plates? Let's assume the first ...
2answers
200 views

### Energy of particle in electric field

I'm taking a physics class and the professor teaches us really basic things in lecture and then gives homework way beyond what he taught in lecture. Obviously I need to find some resource other than ...
1answer
300 views

### Does the electric field inside a sphere change if point charge isn't in center?

As i understood , if you have a point charge in the center of a hollow conducting sphere then the electric field inside it, is zero because the charge distribution is spherically symmetric. But ...
1answer
288 views

### Non conducting charged planes

I have two parallel non conducting charged planes with opposite charges $6\mu C/m^2$, area $A = 3m^2$ and distance between the planes $d = 0.004 m$. I know the potential between these two planes is ...
1answer
433 views

### What's the electric field with a point charge not in the center of the sphere? [closed]

That's a hollow conducting sphere link My charge is at P (10uC). R = 0.15m. PS = 0.05m. DS = 0.35m. What's the electric field at point D?
0answers
22 views

### Electric field outside nonconducting sphere [duplicate]

An electric charge $Q$ is distributed through out a nonconducting sphere of radius $r_ 0$ and has a spherical cavity of radius $r_1$ centered at the sphere's centre. Assume the charge $Q$ is ...
1answer
884 views

### Electric field due to nonconducting sphere

For calculating electric field outside a nonconducting sphere with a hollow spherical cavity. When I use the rule (Charge density= $dQ/dV$), I don't know exactly what is $dV$, is the volume here ...
1answer
332 views

### Electric field strength between 2 positive charges [closed]

I'm having a lot of trouble trying to solve this problem: Three identical point charges of magnitude $+1.0$ $mC$ are located at the corners of a square that is $1.0$ $m$ on a side. A point charge of ...
1answer
457 views

### Finding the Electric Field (and other information, besides)

The problem I am working on is: Two parallel plates having charges of equal magnitude but opposite sign are separated by 29.0 cm. Each plate has a surface charge density of 33.0 nC/m2. A proton is ...
1answer
300 views

### Finding the electric field

The charge per unit length on a long, straight filament is -91.9 µC/m. (a) Find the electric field 10.0 cm from the filament, where distances are measured perpendicular to the length of the ...
1answer
75 views

3answers
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### “Find the net force the southern hemisphere of a uniformly charged sphere exerts on the northern hemisphere”

This is Griffiths, Introduction to Electrodynamics, 2.43, if you have the book. The problem states Find the net force that the southern hemisphere of a uniformly charged sphere exerts on the ...