Electric charge Definition and 275 Threads

Homework Statement (Note: Don't worry about significant digits. I just want to be able to do the question and will worry about significant digits on the exam.) In the figure below, a non-conducting spherical shell of inner radius a=2.00cm and outer radius b=2.40cm has (within its...

The basic law of electric charge fields is that like charges repel and unlike charges attract. This does not come out of the equations but is inserted as just an empirical observation that must be allowed for, is it not ? Am I missing something here? Compare gravity that is always an...

I have not found a discussion open on this, and I would like to know if anybody has an opinion. My questions are triggered by the 0802.2563 arXiv paper (Meson Clouds and Nucleon Electromagnetic Form Factors by G. Miller). It has long been believed that the neutron electric charge density is...

Three parallel, infinite, uniformly charged planes are arranged as shown in Figure 24.32. (it looks just like it's described. The middle plate is positive sigma, the outer plates are both negative sigma.) Homework Statement A small hole passes through the middle plane. At t=0 an...

Two identical conducting spheres, fixed in place, attract each other with an electrostatic force of 0.108 N when separated by 50.0 cm, center-to-center. The spheres are then connected by a thin conducting wire. When the wire is removed, the spheres repel each other with an electrostatic force...

Homework Statement http://img155.imageshack.us/img155/5661/q2gf2.jpg The Attempt at a Solution I got the first part of the question correct but for some reason I can't get the second one. I know I did it correctly but its not working. All the forces acting on particle 2 are from...

Homework Statement http://img210.imageshack.us/img210/3239/q1ae6.jpg The attempt at a solution Kq1q3/(L+x)2 = Kq2q3/(x)2 q1/(L+x)2 = q2/(x)2 I came up with the question above. But when I plug in the numbers I get 2 different answers. For x, I got -7.363450837 and...

Coulomb's Law Problem - Please Help Homework Statement Two positive charges +Q are held fixed a distance d apart. A particle of negative charge -q and mass m is placed midway between them, then is given a small displacement perpendicular to the line joining them and released. Show that the...

[SOLVED] Electric Charge Homework Statement Two point charges q and 4 q are distance L apart and free to move. A third charge is placed so that the entire three-charge system is in static equilibrium. What is the magnitude of the third charge? Homework Equations F = kq1q2 / r^2 k ~=...

Net Electric Charge...Please help! Homework Statement What is the net electric force on charge A? (s=1.41 cm, q1=1.1 nC, q2=0.72 nC, q3=5.21 nC. Force is positive if it points to +x direction.) Homework Equations F = (K * Q * Q) / r^2 The Attempt at a Solution F2on1 = (K * Q1 * Q2) / r^2...

[SOLVED] electric charge problem Homework Statement Two identical small metal spheres with q1>0 and magnitude of q1>magnitude q2 attract each other with a force of magnitude 74.9mN. They are 2.47 m apart. The spheres are then brought together until they are touching. At this point, the...

[b]1. A system of 1525 particles, all of which are electrons or protons, has a net charge of -5.456 x 10^-17. a) how many electrons are in the system? b) what is the mass of the system [b]2. mass of electrons is 9.11 x 10^-31. charge of electron is 1.60 x 10^-19 [b]3. i...

Homework Statement You have an electrically charged sphere. The strength of an electric field 0.1 m away from the center of the sphere is 30,000 N/C. The radius of the sphere is 0.05 m. What is the electric charge (Q) of the sphere? Homework Equations E = F/q - E =...

hi there, i've read books and some web sites and I'm wondering this electric charge? Is it something physical (compose of matter)? some say its the one causing the electric field, by analogy, is it like mass has something to do with gravity? thank you

what does this mean?? "a smallest unit of electric charge of which other units are multiples" The smallest unit of electric charge is q. i don't understand the rest..

Homework Statement The atmostspheric electric fields at heights of 100m and 1000m above the surface of the eartg are 110 v/m and 25 v/m respectively and are directed downwards. Evaluate the averge electric charge per unit volume in the atmostsphere between these heights. Express your result...

Homework Statement 38. Particles 2 and 4, of charge -e, are fixed in place on the y axis, at {y}_{2} = -10.0 cm and {y}_{4} = 5.00 cm. Particles 1 and 3, of charge -e, are placed on the x-axis and can be moved along the x axis. Particle 5, of charge +e, is fixed at the origin. Initially...

Homework Statement Electric Charge Problem with Unit Vectors. 20. In Fig. 21-29, particles 1 and 2 of charge q_{1} = q_{2} = +3.40{\textcolor[rgb]{1.00,1.00,1.00}{.}}x{\textcolor[rgb]{1.00,1.00,1.00}{.}}10^{-19}{\textcolor[rgb]{1.00,1.00,1.00}{.}}C are on a y-axis at distance d = 17.0 cm...

Homework Statement A charge is moved from one place to another in an electric field. In which of the following situations will the change in potential energy be NON-ZERO? True False the charge does not move at all True False the charge is only moved perpendicular to all electric field...

Homework Statement 13. In. Fig. 21-26, particle 1 of charge +1.0 \muC and particle 2 of charge -3.0 \muC are held at separation of L = 10.0 cm on an x axis. If particle 3 of known charge q_{3} is to be located such that the net electrostatic force on it from particles 1 and 2 is zero, what...

Hit enter a bit too fast for the title. TITLE: Electric Charge Problem - Book Error? Homework Statement 6. In Fig. 21-22, four particles form a square. The charges are q_{1} = q_{4} = Q and q_{2} = q_{3} = q. (a) What is Q/q if the net electrostatic force on particles 1 and 3 is...

I'm currently doing electricity in my high school physics. What is the difference between 'negative electric charges' and 'electrons'?:confused:

I got this problem wrong in my text's student companion website, but I don't understand why. Could someone let me know what went wrong? Homework Statement What are the horizontal and the vertical components of the resultant electrostatic force on the charge in the lower left corner of...

I've never been good at "Find the maximum whatever" (Area, charge in this case, etc...) type problems, so I could use some coaching on this one. Homework Statement Of the charge Q initially on a tiny sphere, a portion q is to be transferred to a second, nearby sphere. Both spheres can be...

Three charges, Q1, Q2, and Q3 are located in a straight line. The position of Q2 is 0.279 m to the right of Q1. Q3 is located 0.180 m to the right of Q2. In the above problem, Q1 = 1.90 × 10-6 C, Q2 = -2.65 × 10-6 C, and Q3 = 3.18 × 10-6 C. Calculate the total force on Q2. Use a plus sign for a...

Homework Statement Figure a -q1(+)------q2(+)- x (Just the X axis with two positively charged particles at the opposite ends of it, basically) The figure shows two positively charged particles fixed in place on an x axis. The charges are q1 = 1.60 x 10^-19C and q2 = 3.20 x 10^-19C, and the...

When two charged metal spheres are brought together (in a Wimshurst machine), a spark occurs at a distance of 1.5cm. An electric field of 30,000V per cm is required to cause a spark. I need to work out the charge on the two balls, assuming (I think) it is equal on both. I know how to...

Homework Statement Calculate the magnitude and direction of the Coulomb force on each of the three charges shown in Figure P15.10. http://www.webassign.net/sf5/p15_10.gif thats 3 cm if its to small to see. 6.00 µC charge Magnitude 1.50 µC charge Magnitude -2.00 µC charge...

Homework Statement A ring-shaped conductor with radius a = 2.20 cm has a total positive charge Q = 0.123 nC uniformly distributed around it. (Question relevant to main problem) (a)What is the magnitude of the electric field at point P, which is on the positive x-axis at x = 35.0 cm...

Hi, my name is Cory. I need a little help with one of my AP physics assignments, dealing with Electric Charge, Forces and Fields. I got most of the problems, however here are a few I could use some help / be walked through on. Problem 36) On average, the electron and proton in a hydrogen...

Hi, Any help on this would be appreciated. 1. If you bring a positively charged insulator near one of two metallic spheres that are in contact and then separate the spheres, what charge will the sphere further away from the insulator have? 2. Homework Equations - none 3. I...

Since there's another thread on the same subject in the GR forum, but on this forum about 8 months ago an interesting discussion on the same subject took place, https://www.physicsforums.com/showthread.php?t=114620, i want to draw everyone's attention on the post \#24 in that thread in which the...

Positive charge +Q is distributed uniformly along the +x-axis from x=0 to x=a. Negative charge -Q is distributed uniformly along the -x-axis from x=0 to x=-a. a). A positive point charge q lies on the positive y-axis, a distance y from the origin. Find the force (magnitude and direction) that...

Would someone be so kind to check if I am doing this properly. I'm confused on the units, as it doesn't seem to be coming out properly. Q) Assuming that the electric field intensity is \vec E = \hat x 100 x \,\,(V/m) , find the total electric charge contained inside a cubical volume 100 \,\...

Hey, I thought I did this correctly and my answer turned out incorrect. Here's the problem: http://synthdriven.com/images/deletable/help.jpg" This is what I did: In order to use Coloumb's Law, I need r, the distance between the two charges. \arcsin{4}=\frac{x}{0.24m}...

The magnitude of each of the charges in Figure 18.21 is 9.40 10-12 C. The lengths of the sides of the rectangle are 3.00 cm and 5.00 cm. Find the magnitude of the electric field at the center of the rectangle in Figures 18.21a and 18.21b. I know figure a is 198.22, but I can't seem...

Last question I promise,,,, A uniformly charged disk has a radius of 2.5 cm and carries a total charge of 4*10^-12C. Find the electric field on the x-axis at a distance of 20cm away. I used the equation: Ex = (sigma/ (2*Eo)) * (1 - ( 1/ sqrt( ( R^2/x^2) + 1)) this is what i...

Each quare centimeter of the surface of an infinite p;ane sheet of paper has 2.5 X 10^6 excess electrons. Find the magnitude and direction of the electric field at a point 5 cm from the surface of the sheet, if the sheet is large enough to be treated as an infinite plane. This is an odd...

Just a quick question, what is the difference between electric charge and electric potential energy?

I'm rasining my question in QP on a suggestion made at relativity forum: Why is charge invariant under Lorentz transformation. Is there a fundamental and theoretical answer to this question? (not the experimental "that's the way nature works") Can QED answer question? Or should I look for an...

Consider an air filled parallel plate capacitor with plate area A and gap width d. The plate charge is Q. The total energy stored in the capacitor is given by U= Q^2 *d /2 E_o A. With the battery connected, fill the gap by a slab with the dielectric constant k. Given : E= 70 V, k= 3.8, d=0.8 mm...

Identical isolated conducting spheres 1 and 2 have equal charges and are separated by a distance that is large compared with their diameters. The electrostatic force acting on sphere 2 due to sphere 1 is F and the force acting on sphere 1 due to sphere 2 is -F'. Suppose now that a third...

http://img90.imageshack.us/img90/358/electricforce8yv.png I know how to do the first question. The second question is what's troubling me. I don't know where the forces are supposed to be directed (i.e. to which charge)... basically i don't understand what I'm finding out. Any incite...

A small plastic ball of mass 6.10 10-3 kg and charge +0.150 µC is suspended from an insulating thread and hangs between the plates of a capacitor (see the drawing). The ball is in equilibrium, with the thread making an angle of 30.0° with respect to the vertical. The area of each plate is...

ok here are the question i just need to know how to set them up and work them out this is due tomorrow night at like 12 oclock and my teacher hasnt explained it very well can someone just work it out for me in the equation or just eplain what to do or maybe do one anything will help thanks alot...

I'm having problems figuring this one out. Some guidance would be great! Thanks! Particles of charge Q1 = +75 µC, Q2 = +44 µC, and Q3 = -80 µC are placed in a line (Fig. 21-46). The center one is 0.35 m from each of the others. Calculate the net force on each charge due to the other two...

(src: Intro to Electrodynamics, Griffith, Problem 1.46a) Q: Write an expression for the electric charge density \rho (r) of a point charge q at r^'. Make sure that the volume integral of \rho equals q. Now, Closest I can seem to come up with is...

I am getting stuck trying to find the total electric charge on the annulus. The Question reads: "A thin disk with a circular hole at its center, called an annulus, has inner radius R_1 and outer radius R_2. The disk has a uniform positive surface charge density, sigma, on its surface. Determine...

In a uniformly charged ring of radius r, if there is an imaginary line from the center of the ring extending outward || || || ||-----------------X-------------------------------> infinity || || || At the center of the ring I am told the charges cancel so the net charge is zero. And at...

A proton is on the x-axis at x= 1.6nm. An electron is on the y-axis at y=0.85nm. Find the net force the two exert on a helium nucleus (charge + 2e) at the orgin. there's a solution from the book, but i don't really understand it: k = 9X10^9 N*m^2 and e=1.6*10^-19 Coulomb force of the...