Electric fields Definition and 483 Threads

[b]1. Two point charges of equal magnitude are 8.4 cm apart. At the midpoint of the line connecting them, their combined electric field has a magnitude of 45 N/C. Find the magnitude of the charges. [b]2. E=k(q)/r^2 [b]3. I've tried 45= 8.99x10^9(q)/(.084)^2 and got q to equal 35...

I've been reading a section on induced dipoles in Griffiths, It says that although an atom as a whole is electrically neutral, there is a positively charged core and a negatively charged electron cloud, and when the atom is within an electric field the nucleus is pushed in the direction of the...

Negative charge - Q is distributed uniformly around a quarter-circle of radius a that lies in the first quadrant, with the center of curvature at the origin. Find the x-component of the net electric field at the origin. Find the y-component of the net electric field at the origin.

Homework Statement An electron is released from rest in a weak electric field given by vector E = -2.40 10-10 N/C jhatbold. After the electron has traveled a vertical distance of 1.8 µm, what is its speed? (Do not neglect the gravitational force on the electron.) Dont even know where...

This isn't the normal kind of homework question, I'm more hoping you can help me fill in the missing steps from this example given by our professor in the class notes. The below example is supposed to assist me in solving my homework problem, I understand everything except the answers circled...

Hey I'm a new time member but I hope to use this forum for my college Physics 2 class, anyways: 1. Question: Two charges are D = 2.5 m apart and lie on the x-axis. What must be the magnitude of the charge on the right one, Q2, (in C) so that the electric field is zero at x = 1.75 meters. Let...

Can anyone find a website that shows you how to calculate the electric field by integration for a evenly distributed disk and a hollow ring? I tried figuring it out myself but all the websites I found skipped many steps on the math. Thanks!

"Mach's principle" for electric fields I know it's terrible to draw conclusions from similarities, and gravity and electromagnetism have a particularly bad wrap for this. I made this post recently: https://www.physicsforums.com/showpost.php?p=2841591&postcount=29 And it got me wondering if...

Homework Statement A 0.10 g honeybee acquires a charge of +23 pC while flying. (a) The electric field near the surface of the Earth is typically 100 N/C, directed downward. What is the ratio of the electric force on the bee to the bee's weight? (b) What electric field strength and...

Homework Statement An electromagnetic wave in a vacuum /w magnetic field of 265 mG. If the wave is spatially confined to a beam with a diameter of .75mm, how much energy is measured by a photodetector with an active area with diameter 5 cm in one second. The Attempt at a Solution...

Homework Statement The magnetic field is uniform and out of the page inside a circle of radius R, and is essentially zero outside the circular region (see the figure). The magnitude of the magnetic field is changing with time; as a function of time the magnitude of the magnetic field is...

I know the template needs to be used but i don't want answers i need help starting this. What equation do i use? Here is the question: In a particular region of space, the magnetic and electric fields have energy densities of 0.2 J/m3 and 4 J/m3 , respectively. Calculate the strength...

Homework Statement http://img532.imageshack.us/img532/1460/problemjh.png Homework Equations Electric field from infinite plane: E = \frac{\sigma }{2\varepsilon _{0}} The Attempt at a Solution I'm pretty sure that at region 2, the total electric field is 0 since all the charges on the...

Homework Statement 108 electrons are equally spaced around a circle of radius 10.0 cm. What is the electric field at the center of the circle? What would be the electric field be at the same location if one electron was removed? Homework Equations \begin{flalign*}E & = & & k \...

Homework Statement Each of the protons in a particle beam has a kinetic energy of 3.25 x 10^-15 J. What are the magnitude and direction of the electric field that will stop these protons in a distance of 1.25 m? Homework Equations Felectric = kC (q*q/r^2) Electric Field= Felectric/q...

Homework Statement An object with a net charge of 24 x 10^-6 Coulombs is placed in a uniform electric field of 610 N/C, directed vertically. What is the mass of this object if it floats in this electric field? Homework Equations Felectric = kC (q*q/r^2) Electric Field= kC (q/r^2) E=...

Hi People all know that a neutral atom has no net charge. Well, does that mean that it neither creates an electric field nor is affected by any electric field? I wonder whether it's correct or not, because the distance between a test charge outside this atom is closer to its electrons...

Homework Statement Figure 1 shows a pair of parallel metal plates, A and B, fixed vertically 20mm apart with a potential difference of 1500V between them. (a)(i) Draw the electric field lines in the space between the plates and calculate the electric field strength at point P. (a)(ii)Sketch...

Homework Statement A proton (q = 1.6×10−19 C, m = 1.67×10−27 kg) moves at 300 ms−1 along a line midway between the x and z axes. There is a magnetic field of 1T along the x axis and an electric field of 2000 Vm−1 along the y axis. What is the force on the proton and what is its acceleration...

Jus chek out careful when we have uniform electric charge distribution along wire or a sphere etc! Is there no any interaction between the charges in that uniform distribution! then look at the capacitor we only see straight field lines from positive charged plate to the negative charged...

If an electric field causes 2 previously stationary charges to accelerate(let's say that there was something inhibiting their movement that has now been removed) toward or away from one another, what type of field is between them, electric or magnetic?

*first time posting on here* Hi, firstly I am a high school junior taking physics and I find it very interesting and plan to major in it. Now, today my teacher was explaining electric fields and said that all charged objects generate them around themselves. He then said that fields themselves...

Hi All, I'm reading about special relativity but I'm having a very difficult time trying to understand what the author is saying. Imagine a very large magnet mounted by railroad tracks such that a moving train passes through it. On a moving train is a loop of wire. Now as train passes...

Homework Statement In the figure below, an electron is shot at an initial speed of v0 = 2.25 × 106 m/s, at angle θ0 = 20.0o from an x axis. It moves through a uniform electric field = (5.04 N/C) . A screen for detecting electrons is positioned parallel to the y axis, at distance x = 3.23 m...

Homework Statement I am looking to calculate the horizontal and vertical components of an electric field at the point of the oil drop can someone tell me if I am on the correct tracks by using the following equation. Homework Equations E=kQ/r2 The Attempt at a Solution

1. Three posative charges +Q lie on the corners of a square which is rotated 45 degrees with respect to the x-axis. Calculate the electric field at the origin, in terms of the variables Q and a. I think this question is much easier than I think it is but I'm stuck on it. There is a picture...

Homework Statement The electric field midway between two equal but opposite point charges is 894 N/C, and the distance between the charges is 17.2 cm. What is the magnitude of the charge on each? Homework Equations E = Fe/q Fe = kq1q2/r^2 The Attempt at a SolutionElectric field = k*q/r^2 =...

A 40 Micro Coluomb test charge is placed in an electric field produced by a 5 Coloumb charge. It expierences a 6 Newton force. What is the strength of the electric field at this point? If the test charge has a mass of 3 x 10 ^ -20 Kg, what acceleration does it expierence? I Think I could...

Homework Statement The source charge (the magenta circle at the origin) is a positive charge. A particle whose charge is -6e-09 C is placed at location D. 1. The electric field at location D has the value < -8000, 8000, 0 > N/C. What is the unit vector in the direction of E at this...

Hi all .. I was studying this electric field due to infinite non conducting sheet having uniformly distributed positive charge..Electric field due to it is of same direction and magnitude at any point..Which is called uniform electric field!I understood why direction of field is always...

I am struggling to grasp the concept of the electric field between two opposite charges. I know that the field is strongest closest to the charge and gets weaker further away from the charge. I also know that the electric field lines go from positive to negative and that they are perpendicular...

Homework Statement 1. If two plates, 1.0 cm by 1.0 cm, with charges of −2.30 µC and +2.30 µC, what is the magnitude of the electric field at b? +++++++++++++ ...b ----------------- 2. A uniform electric field of strength E = 4.80×10^4 N/C is observed in the region adjacent to a large...

Homework Statement Two very large horizontal sheets are 4.25 cm apart and carry equal but opposite uniform surface charge densities of magnitude \sigma. You want to use these sheets to hold stationary in the region between them an oil droplet of mass 364 \mug that carries an excess of five...

Homework Statement What work is needed to move an electron from (0,5m,0) to (0,0,8m) in an electric field of E = {25, -30, 0} x 10^3 V/m? Homework Equations W = Change in U = Q* Change in V The Attempt at a Solution I calculated Change in V = -E* change in r. Change in r I got...

Throughout space there is a uniform electric field in the -y direction of strength E = 540 N/C. There is no gravity. At t = 0, a particle with mass m = 3 g and charge q = -17 µC is at the origin moving with a velocity v0 = 25 m/s at an angle θ = 25° above the x-axis. (a) What is the magnitude...

Hi Got a question, hoping someone can give a good explanation for. We all know that large static uniform electric fields have the potential to ionize. (Dielectric breakdown of Air - Static Electricity Shock). In the Quantum picture, why does this occur. Take for instance the photo...

This image confuses me a tad. We have the n-type (negative) silicon and the p-type (positive) silicon plates. We put the plates together. The electrons are in a rush to fill the positive "holes" on the p-side, and the positive holes are in a rush to to the n-side, to the electrons. Between...

I'm an HVAC engineer and my company has tasked me with researching a variety of water treatment products (for cooling towers). One of which is Dolphin Water Care (http://www.dolphinwatercare.com/Index.aspx) The technology seems a little fishy to me, so I wanted to see if anyone could tell me...

A particle with charge +7.88 μC is placed at the fixed position x = 3.00 m in an electric field of uniform strength 300 N/C, directed in the positive x direction. Find the position on the x-axis where the electric field strength of the resulting configuration is zero. I don't understand...

1. Homework Statement In a laboratory, a particle of charge -6C is held stationary because it is placed in an electric field E=(0,0,-15)N/C which suspends it against gravity. What is the mass of the particle? Give answer in kg. 2. Homework Equations I THINK E= F/q F= ma or F= G m1 m2 /...

Is there any effects on electric fields or magnetic fields in a Gravitational field? I know that electro-magnetic waves(photons) are effected from the bending of space and time, from gravity. however i was just wondering how magnetic fields or virtual photons respond to gravity. Any...

I was having some trouble understanding how an electric dipole creates an electric field around it? Shouldn't the two oppositely charged particles in the dipole totally cancel out their electric fields? Well, I figured out that the two particles only exert a force on each other...

Homework Statement Would it be possible for someone to check my answer to this past examination question, as I am not sure I'm doing them correctly! Thanks in advance. A negatively charged oil drop, mass 2.4 x 10^–12 kg, is stationary between two horizontal metal plates spaced 1 cm apart...

This is a question that I'm doing as part of revision for my January mocks. Being bad a algebra in general, I'm stuck. The answer is a worked example and I still don't understand it, so I'm feeling very silly. Homework Statement Charges of +4C and +8C are placed 1.00m apart. At what...

Hello, First of all, I'm not sure if this is in the right section, and I know it's probably a very basic question compared to all you levels of knowledge. So please if it isn't in the right section, let me know where I should post it, and if not thanks in advance for the help. I'm trying...

I can understand that in the middle of an empty conductor sphere the electric field is worth 0. But I don't understand why it is also 0 in the interior of the sphere at any point. I know that by Gauss' law it is 0 but I don't grasp it. For instance if you chose a point very close to the...

why is there a different equation for force in a uniformed electric field F=E/Q as opposed to the electric field between a pair of oppositely charged plates F=EQ ? I thought it would be the same as the field between a pair of oppositely charged plates are also relatively uniformed, in the...

Homework Statement A sphere of radius R=10 cm made of insulating material has a uniform charge density p=100 C/m-3 a)Find the magnitude of the electrical field at a distance r<R, using Gauss' Law.What is the value of the electric field at r=5 cm? b)What is the total charge on this...

Im curious about an electric field (somewhere of radius s) inside a solid sphere (radius a) such that: \int E.da=E4\pi s^{2} and Q = \frac{\rho 4\pi s^{3}}{\epsilon_{o}3} What is the difference between using each coordinate system to solve for E? It's just that I've really had to teach...

Homework Statement A long solenoid has a diameter of 12.0 cm. When a current i exists in its windings, a uniform magnetic field = 25.0 mT is produced in its interior. By decreasing i, the field is caused to decrease at the rate of 6.30 mT/s. Calculate the magnitude of the induced electric...