Tagged Questions
0
votes
1answer
91 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 ...
1
vote
1answer
163 views
Finding Electric Field outside a Charged Cylinder
I'm trying to solve a problem that involves finding the electric field due to a uniformly cylinder of radius $r$, length $L$ and total charge $Q$. Well, my thought was: if I am to use Gauss' Law, I'll ...
1
vote
1answer
122 views
Finding the electric field on a point (x,y,z) using Coulomb's Law
Using Gauss' Law, the answer is $$\frac{Q}{4 \pi \epsilon R^2}.$$
However if I were to do the integration using Coulomb's Law, I get
$$ \int_0^{2\pi} \int_{0}^{\pi}\int_r^a \frac{\rho \sin\theta dR ...
1
vote
2answers
212 views
Find the quantity of charge - given potential function
A potential function is given by $V(r)=\frac{Ae^{-\lambda r}}{r}$ Find charge density and hence charge.
I first took the gradient of potential to get $\vec{E}(r)=\frac{Ae^{-\lambda ...
4
votes
1answer
932 views
Shouldn't the electric field in a solid insulating sphere be linear with radius?
I am a senior in High School who is taking the course AP Physics Electricity and Magnetism.
I was studying Gauss's laws and I found this problem:
A solid insulating sphere of radius R contains a ...
1
vote
2answers
144 views
Is it really to solve problem below by using, in the main, Gauss law?
There is an infinite cylinder surface which uniformly charged along and has a surface charge density, which can be represented as
$$
\sigma = \sigma_{0}cos(\varphi ),
$$
where $\varphi$ - polar angle ...
0
votes
1answer
142 views
Gauss's Law in action
Need someone to tell me if I got this done correctly
(a) Draw Gaussuian cylinder inside the black cylinder to find charge enclosed
$Q_{en} = Q(\frac{r}{a})^2$
Apply Gauss's Law
$E2\pi r \ell = ...
2
votes
2answers
561 views
Electric potential of sphere
(a) I am a little confused about this part. The point at A to B isn't radial. The electric field is radially outward, but if I look at the integral
$$\int_{a}^{b}\mathbf{E}\cdot d\mathbf{s} = ...
0
votes
1answer
76 views
Gauss' Law… Neglect Edge effects [closed]
Two Large Metal plates of area $1.0$ $m^2$ face each other. They are $5$ $cm$ apart and carry equal and opposite charge on their inner surfaces. If $E$ between the plates is $55$ $N/C$, what is ...
0
votes
2answers
3k views
Using Gauss's Law to calculate electric fields between plates
I have two earthed metal plates, separated by a distance $d$ with a plane of charge density $\sigma$ placed a distance $a$ from the lower plate. I want to derive expressions for the strength of the ...
0
votes
1answer
72 views
Flux if there were only one type of charge in the universe
There was this question that i saw in a book and it also had an answer given.
The Question was:
If there were only one type of charge in the universe, then:
$\phi = \oint ...
4
votes
4answers
2k views
Infinitely charged wire and Differential form of Gauss' Law
I have tried calculating the potential of a charged wire the direct way. If lambda is the charge density of the wire, then I get
$$\phi(r) = \frac{\lambda}{4 \pi \epsilon_0 r} \int_{-\infty}^\infty ...
4
votes
3answers
960 views
“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 ...
5
votes
3answers
806 views
Charge Distribution on a Parallel Plate Capacitor
If a parallel plate capacitor is formed by placing two infinite grounded conducting sheets, one at potential $V_1$ and another at $V_2$, a distance $d$ away from each other, then the charge on either ...
1
vote
1answer
269 views
Electric Flux Density - Ring Charge
A ring placed along $y^{2}$ + $z^{2}$ = 4, x = 0 carries a uniform charge of 5 $\mu$C/m. Find D at P(3,0,0)
Should I be using Gauss's Law to solve this problem? I was considering using a spherical ...
-2
votes
1answer
4k views
Electric field due to nonconducting plastic sheets [closed]
Two very large, nonconducting plastic sheets, each 10.0 cm thick, carry uniform charge densities $\sigma_1, \sigma_2, \sigma_3$ and $\sigma_4$ on their surfaces (the four surfaces are in the ...
1
vote
0answers
152 views
Flux from a point charge at the center of a cube [closed]
A charge of $145 \times 10^{-6} C$ is at the center of a cube of edge $.5m$. What is the flux through each face of the cube?
I would write what I have so far, but I don't know how to use MathJax.
2
votes
2answers
313 views
Gauss' law giving zero field where field is not zero?
Two plastic sheets with charged densities as shown:
I'm trying to find the field at $B$. I obtained the correct answer by adding up the fields created by each charge density. But I realized that ...
