Electric Definition and 1000 Threads

The approach used in the book uses polar coordinates. I was wondering if my approach would still be correct. I set up the problem such that the midpoint of one face of the cylinder is at the origin while the midpoint of the other end's face is at the point (##l##,0). The surface area of the...

Feynman's Lectures, vol. 1 Ch. 28, Eq. 28.3 is ##r'## is the distance to the apparent position of the charge. Feynman wrote, "Of the terms appearing in (28.3), the first one evidently goes inversely as the square of the distance, and the second is only a correction for delay, so it is easy...

Attached is the subsection of the book I am referring to. The previous section states that the electric field magnitude at any point set up by a charged nonconducting infinite sheet (with uniform charge distribution) is ##E = \frac{\sigma}{2\epsilon_0}##. Then we move onto the attached...

Well, I really don't understand what is the use of the hint. I try to solve this problem with Coulomb's Law and try to do in spherical coordinates and got very messy infinitesimal field due to the charge of infinitesimal surface element of the sphere. Here what I got: $$\vec{r}=\vec{r_P} +...

I have a lot of questions about this single concept. You don't have to answer the questions in the order that I ask, if it is convenient to answer them in a different order. 1. When the dipole moment ##\vec{p}## is in the same direction as the electric field (uniform) it has the least potential...

A single electron sitting in a void has an electric field that spreads out evenly in all directions as far as there is open empty space to allow it, is this roughly a correct statement? Let's say we now introduce a singe proton into the void, 100 miles from the electron - it will also have an...

Maybe I should use this?

I am considering getting a physics bachelors with a minor in electric and computer engineering. I want to study computers and the hardware behind them, but also study the physics aspects of them. I also am considering going to graduate school to get a masters or PhD and doing research into...

The question is like this: The solution is like this: However, according to the equation for ##E_{dip}## , what I think is that it should be: $$E=\frac {1}{4 \pi \epsilon_o} \frac {qd}{d^3} \hat {\mathbf z} $$, where I take the centre of the sphere in figure 2 as the centre of the...

I sort of understand the meaning of this integral, but I don't know how to evaluate it. I have never evaluated a volume integral. It would be very helpful if someone could explain in other words what this integral means and give an example evaluating it. This is from Purcell's Electricity and...

Tecd

Let's say I place a positive point charge inside a hollow conducting sphere. If we take a Gaussian surface through the material of the conductor, we know the field inside the material of the conductor is 0, which implies that there is a -ve charge on the inner wall to make the net enclosed...

I was reading chapter 3 of this book https://blackwells.co.uk/bookshop/product/Superconductivity-by-James-Arnett/9780198507567, which is a brief introduction to superconductivity. It is stated that inside a superconductor the Electric filed is always zero. This is deduced from the equation...

Today when I am reading Griffith's electrodymamics on surface charge and force on conductors, I have come across two very ambiguous terms: electric field at the surface and immediately outside the surface. The context of these two words is as follows: The electric field immediately outside is...

Hey, I am struggling a bit, als I try to solve this problem - I‘d say all five statements are correct, but it is said, that one must be incorrect

The Dirac equation for an electron in the presence of an electromagnetic 4-potential ##A_\mu##, where ##\hbar=c=1##, is given by $$\gamma^\mu\big(i\partial_\mu-eA_\mu\big)\psi-m_e\psi=0.\tag{1}$$ I assume the Weyl basis so that $$\psi=\begin{pmatrix}\psi_L\\\psi_R\end{pmatrix}\hbox{ and...

Good afternoon guys, I was making some researches about building my own EV and its' specifications but I have a few no direct answered questions and some of them I humbly ask the help for you guys, based on the configuration example below. Considering that I hypothetically have an electric DC...

The attached file is the coordinate system I've used a) $$\vec{E}=\dfrac{\vec{F_e}}{q}=\dfrac{1,10\cdot{10^{-13}}\hat{j}\;N}{1,6\cdot{10^{-19}}\;C}=6,88\cdot{10^5}\hat{j}\;N/C$$ b) $$\sum{\vec{F_{net}}}=\vec{0}=\vec{F_e}+\vec{F_m}$$...

According to the continuity equation of the electric field (i.e., ▽·Ε = 0) a decrease in cross-section area will increase the electric field strength, Why is that?

The near-range magnetic field ##\vec{B}## of a point charge ##q## at distance ##\vec{r}##, moving at a non-relativistic velocity ##\vec{v}##, is given by $$\vec{B}=\frac{q}{4\pi\epsilon_0c^2}\frac{\vec{v}\times\hat{r}}{r^2}.$$ Faraday's law of induction for the induced EMF ##V_c## in a coil...

So for the Gaussian theorem we know that $$ \frac{Q}{e} = \vec E \cdot \vec S $$ Q's value is known so we don't need to express it as $$Q=(4/3)\pi*(R_2 ^3-R_1 ^3)*d$$ where d is the density of the charge in the volume. I've expressed the surface $$S=4\pi*x^2$$ where x is the distance of a point...

Let point charge q be at y=r. Let there be an infinite conducting plane along the x-axis and z-axis that is neutrally charged. In this case, the method of mirror charges can be used. The plane is replaced by a point charge -q at y=-r. The electric field for y > 0 is the same in both cases...

I've come across a number of problems in elementary probability theory and statistics that can be exemplified as follows: Naturally, real lamps decay over time, so their lifetimes can't be memoryless. With that being said, is the exponential distribution a good approximation for the...

Thanks in advance!

I've got a quick question on the relationship between the kinetic energy of individual electrons and the total electrical energy they create. I have a radioisotope - a beta emitter - which produces electrons with around 1 MeV (1.60218×10-13 Joules / 4.45049×10-17 Watt-hours) of energy. I keep...

Not sure how the problem set up initially as no diagram was provided in the question. Please help me to start with the solution. Your assumptions and educated guess are appreciated.

Hello everybody! I want to check out if I've solved correctly: ##\Delta{V}=-E\Delta{x}## ##\dfrac{\Delta{V}}{\Delta{x}}=-E## ##\dfrac{15\;V}{10^{-2}\;m}=-E## ##1,5\times{10^3}\;N/C=-E## ##\vec{E}## direction it's oriented into the XY plane Thanks!

I couldn't solve the question. Can you help me?

According to the circuit in the figure; Can you calculate the values of the currents I1, I2, and I3. Can you send me a detailed solution to understand?

The problem is symmetric around the z axis, thus the force must be in the z direction only. I tried dividing both rings into differential elements, then integrating through the upper ring to get the z component of the total force on the upper ring due to a differential element of the lower ring...

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?

I've been reading through this paper to try and get a better understanding of how batteries work. The analysis there is fine (they consider a voltaic cell to charge a capacitor in order to derive ##\Delta V=\varepsilon##, and go via an energy route), but it doesn't really touch upon the fields...

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

Electric potential energy at initial: Ee=kq1q2/r =(9 ×10 ^9×1.5×10^-6×(-5)×10^-6)/0.1 =-0.675J Electric potential energy at the closer point: Ee=kq1q2/r =(9 ×10^9×1.5×10^-6×(-5)×10^-6)/0.05 =-1.35J Δv=ΔEe/q =(-1.35+0.675)/1.5×10^-6 =4.5×10^5V or: Initial position...

I have to estimate the electric dipole moment of an NV center in units of Am. I know that for a regular electric dipole moment it can be estimated using p=ed. With e=1.6*10^-19 and d=0.1 nm (interatomic distance), this however is in units Cm. I don't know how to go to Am

Why is electric current not a vector while electric current density is a vector? What's the intrinsic difference between the two through that surface integral?

I want to know ohm's second law i search many times about it but every time the result is about ohm's first only, so can anyone help me??

I think the right solution is c). I'll pass on my reasoning to you: R=6\, \textrm{cm}=0'06\, \textrm{m} \sigma =\dfrac{10}{\pi} \, \textrm{nC/m}^2=\dfrac{1\cdot 10^{-8}}{\pi}\, \textrm{C/m}^2 P=0'03\, \textrm{m} P'=10\, \textrm{cm}=0,1\, \textrm{m} Point P: \left. \phi =\oint E\cdot...

a) \vec{F}=\vec{E}\cdot q \phi =\oint \vec{E}d\vec{S}=\oint \vec{E}d\vec{S}=\underbrace{\oint \vec{E}d\vec{S}}_{\textrm{FACES } \perp}+\underbrace{\oint \vec{E}d\vec{S}}_{\textrm{FACES } \parallel}=0+\oint EdS\cdot \underbrace{\cos 0}_1= E2S \dfrac{Q_{enc}}{\varepsilon_0}=\phi \left...

My first impression was the electric field is 0 at the center of the sphere, but it turned out not the case. My understanding when problems refer surface charge density, is that the charge exists only on the surface and it is hollow inside the sphere. Am i correct? Using the electric field...

I have attached my solution to this problem but I think I got the wrong answer.

I have drawn a picture of what the induced electric field will look like, and I have determined its magnitude both within and outside of the magnetic field. I was able to get the right answer for part (b) with this information, but I don't understand why the answer for part (c) is 0 J. It...

The net electric field is ## 2dE \cos\theta ## ## dE = \lambda dx/(4\pi\epsilon (x^2 +r^2)) \\ 2dE \cos\theta = 2r\lambda dx /(4\pi\epsilon (x^2 +r^2)^\frac 3 2) \\ E_{net} = 2\lambda r /(4\pi\epsilon) \int_0^a dx /( (x^2 +r^2)^\frac 3 2) \\ E_{net} = 2\lambda r /(4\pi\epsilon) [\frac x...

I tried getting E by dividing volts and distance since I know the distance between the two plates is .352 m but it did not work

I thought it was easy but i am not getting the correct answer The electric field due the point charge q is ## E1 = q/(4\pi\epsilon x^2) ## The electric field due to the thin ring of radius R is considering the electric field due to the element charge dq (dS) ## dE2 = dq/4\pi\epsilon (x^2 + R^2)...

Isn't the superposition principle of electric field just force being addable? Jackson's electrodynamics says it's based on the premise of linear Maxwell's equations. Which support(s) the superposition principle?

Hello everyone, I am dynamically modelling a electric superheater. During the calculation I need to calculate the overall heat transfer coefficient. Can someone tell me which calculation do I need to use to calculate the overall heat transfer coefficient, radiant or convective? Please clear my...

Homework statement: Find the electric field a distance z from the center of a spherical shell of radius R that carries a uniform charge density σ. Relevant Equations: Gauss' Law $$\vec{E}=k\int\frac{\sigma}{r^2}\hat{r}da$$ My Attempt: By using the spherical symmetry, it is fairly obvious...

When you ground something in electrostatics, the potential of that body becomes the potential of the Earth once equilibrium has been reached. In this context, it is usually taken that the Earth is at 0V. There are two possibilities for this. Either the constant of integration is chosen such that...