Coulomb's law Definition and 403 Threads

Homework Statement By what factor must you change the distance between two point charges to change the force between them by a factor of ten? Homework Equations F1=kq1/r^2 F2=kq2/r^2 The Attempt at a Solution F1:F2= 10 r1/r2=sq.root(F2/F1)= 1/sqroot10 I do not understand...

Homework Statement Consider the arrangement of point charges shown below. Calculate the net force on point charge 1 given the arrangement of the point charges and the separation of the charges. 1=2=3=e- 2=e+ r=0.4cm =0.0004m K=9x10^9 Fnet=? Please use this link for an image of...

There are four charges, each with a magnitude of 2.5 microcoulombs. Two are positive and two are negative. The charges are fixed to the corners of a 0.29-m square, one to a corner, in such a way that the net force on any charge is directed toward the center of the square. Find the magnitude of...

Homework Statement In the figure, four particles form a square. The charges are q1 = q4 = Q and q2 = q3 = q. (a) What is Q/q if the net electrostatic force on particles 1 and 4 is zero? Homework Equations F=8.99E9 Nm^2/c^2 [abs(q1)abs(q2)]/r^2 The Attempt at a Solution I made up...

Homework Statement Two equally charged particles are held 3.2*10^(-3)m apart and released from rest. The initial acceleration of the first is 7 m/s^2 and that of the second is 9 m/s^2. If the mass of the first is m1= 6.3*10^(-7) kg, what are a) the mass of the second particle and b) the...

The near identity of Coulomb's law and Newton's law of gravitation is interesting to consider in light of the recent unexpected greater velocity (or acceleration) of deep space probes. If we add a mass term to Coulomb's law and a charge term to Newtons' law, then they are nearly the same...

Styrofoam is a polymer containing carbon and hydrogen. Assume the formula is C8H8. How many molecules are in a 0.2 g styrofoam peanut? How many protons and electrons are in this peanut if it carries no excess charges? How many coulombs of positive and negative charge does this represent? If the...

Homework Statement Homework Equations It's given in the answer box. The Attempt at a Solution Basically, I found that equation for the magnitude of the force experienced from particle 0 by particle 3. I know it to be correct. However, vectors have always confused me, could...

What exactly is meant by universal law? I have read in a book a that Ohm's law is not a univeral law. I somewhat understood that as Ohm's law is not obeyed by all materials and not always. But I read now in another book that Coulomb's law is also not a universal law. Now I am beginning to...

Homework Statement A point charge of -0.35nC is fixed at the origin. Where must an electron be placed in order for the electric force acting on it to be exactly at it's weight. Homework Equations Fe=Kqq/d^2 The Attempt at a Solution All I know is that n is an exponential value of...

!Coulomb's Law! So I have already solved this one before, but I was redoing it fir practice when I encountered something that is troubling me. Depending on how I choose to solve my two equations, I get different results. Surely I am doing something wrong, but I cannot see it. Problem Two...

[SOLVED] Coulomb's Law question - find initial charge Homework Statement Two identical small metal spheres with q1>0 and |q1| > |q2| attract each other with a force of magnitude 55.4 mN. They are separated by a distance of 3.94 m. The radius of each sphere is 40 micro-Newtons. The...

[SOLVED] Question about Coulomb's Law I just solved this a problem in my text: Particle 1 of charge +1.0 uC and particle 2 of charge -3.0 uC are held at a separation L=10.0 cm on an x-axis. If particle 3 of unknown charge q3 is to be placed such that the net electrostatic force on it from 1...

Stupid Charges! Two identical conducting spheres, fixed in place, attract each other with an electrostatic force of .108 N when their center-to-center separation is 50 cm. The spheres are then connected by a thin conducting wire. When the wire is disconnected, the spheres repel each other with...

Homework Statement I really can't see where I am going wrong here. I would latex out my work, but it would take way too long, so I have scanned it in. It should be easy enough to read though. Its NUMBER 7, fig 21-22 Also the blurr says '100 nC' The Attempt at a Solution

Homework Statement Suppose you let identical pith balls come in contact to make q1=q2 would the charges be equal if the pith balls were of different size? Homework Equations F=k(q1)(q2)/r^2 The Attempt at a Solution I would think they wouldn't be, because doesn't the charge...

Homework Statement Particles 2 and 4, of charge -e, are fixed in place on the y-axis at y2=-10.00 cm and y4=5.00cm. Particles 1 and 3, of charge -e, can be moved along the x axis. Particle 5 of charge +e is fixed at the origin. Initially particle 1 is at x1= -10.0cm and particle 3 is at x3=...

this is my first time posting here in the forums right now I am really stuck with this problem i already tried solving it on my own but i can't i will really apreciate any feedback or hint i could use to solve it U_U Estimating Charge Two hard rubber spheres of mass ~20 g are rubbed...

this is my first time posting here in the forums right now I am really stuck with this problem i already tried solving it on my own but i can't i will really apreciate any feedback or hint i could use to solve it U_U Estimating Charge Two hard rubber spheres of mass ~20 g are rubbed...

Homework Statement Two point charges lie on the x-axis. A charge of +7.7 uC is at the origin, and a charge of -4.4 uC is at x = 10.0 cm. At what position x would a third charge q3 be in equilibrium? Homework Equations F = k(q1)(q2)/r^2 The Attempt at a Solution This was how I...

Homework Statement Two small pith balls, each of mass m = 12 g, are suspended by 1.2 m fine (so that we can neglect their mass in this problem) strings and are not moving. If the angle that each string makes with the vertical is q = 42.6, and the charges on the two balls are equal, what is...

[SOLVED] Coulomb's Law The charges and coordinates of two charged particles held fixed in an xy plane are q1 = +3.5 µC, x1 = 3.0 cm, y1 = 0.50 cm, and q2 = -4.0 µC, x2 = -2.0 cm, y2 = 1.5 cm. At what coordinates should a third charge q3 = +5.5 µC be placed such that the net electrostatic force...

From Coulomb's law, as the distance between a charged particle and another charged particle approaches zero, the electrostatic force between the two particles approaches infinite. However, according to Gauss's Law, we know that for a uniformly charged sphere or spherical shell, the charge...

Consider int(E.dA)=q/e, guass law relating the electric field to the charge enclosed. One can also derive (using the more mathematical version of guass' law - involving the double integral) this same formuala for a graviational field. Here the permitivitty constant would be replaced by...

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...

Hi, can you derive Gauss's Law without using Coulomb's Law? If so, how? Thanks

Homework Statement Three point charges are placed at the following points on the x-axis: +2.0 micro Coulombs at x=0; -3.0 micro Coulombs at x=40 cm; and -5.0 micro Coulombs at 120 cm. Find the force on the -3.0 micro Coulomb charge. Homework Equations Coulomb's Law: Fe= k * qq' /...

Gauss's law may be used to derive Coulomb's law. I've never seen it done the other way around. Is this possible? Because I have not seen it, I infer that these forms are not logically equivalent.

Does anyone know when Coulomb discovered his law? And does anyone know when the concept of electric field lines was invented? I know that Faraday created the idea for the magnetic field and I was wondering if it was he who applied it to the electric field or was it someone else? Sources of...

1. Homework Statement Hi, I would appreciate it if someone could help me with this question, I am a n00b here Please and thank you Okay here's the question. The particles have charges Q1 = -Q2 = 100nC and Q3 = -Q4 =200nC and distance a = 5.0cm. What are the x and y components of the...

Title: Scalar form of Coulomb's Law? Homework Statement Homework Equations Coulomb's Law Vector Form: \vec{F}_{12} = {\frac{{{k}_{e}}{{q}_{1}}{{q}_{2}}}{{r}^{2}}{\hat{r}_{21}}} Magnitude Form: |\vec{F}_{12}| =...

Hi guys, these are the final 2 problems that I've been struggling with for the past day. Please help 1. Four point charges are situated at the corners of a square with sides of length a, as in Figure P15.4. Figure P15.4 Find the expression for the resultant force on the positive...

1. The Moon and Earth are bound together by gravity. If, instead, the force of attraction were the result of each having a charge of the same magnitude but opposite in sign, find the quantity of charge that would have to be placed on each to produce the required force. 2. Fe = ke...

Homework Statement Charge 8e-18 C is on the y-axis a distance 2 m from the origin and charge 9e-18 C is on the x-axis a distance d from the origin. The Coulomb constant is 8.98755e9 Nm^2/C^2. What is the value of d for which the x component of the force on 9e-18 C is the greatest...

Homework Statement Three charges are on the x~axis about five cm apart. Charge A is three micro C, charge B is negative four micro C, and charge C is five micro C. What is the effect on B? Homework Equations I have no idea how to solve this or the formula involved. The Attempt at a...

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 treated as particles. For what value of q/Q will the electrostatic force between the two spheres be maximized? Homework Equations...

Actually, this is not a homework question, but more of a concept problem (Sorry I can;t follow the format). We are given that the force of repulsion or attraction between 2 charged objects can be represented by : Fe = (Kq1q2)/d^2. Does this mean that the sum of the force between both objects...

Homework Statement In Fig. 21-26, particle 1 of charge +1.0 microCoulombs and particle 2 of charge -3.0 microCoulombs are held at separation L = 10.0cm on an x axis. If particle 3 of unknown charge q3 is to be located such that the net electrostatic force on it from particles 1 and 2 is zero...

One of Newton's laws(1 or 2) states that every force has an equal and opposite force. Coulomb's law describes subatomic particles interacting with one another. Electrons repel each-other relative to their distance while attracting protons relative to each-other. My question is, will the...

Hello, I'm having problems with the following question: Neutral metal sphere A, of mass 0.10 kg, hangs from an insulating wire 2.0 m long. An identical metal sphere B, with charge -q, is brought into contact with sphere A. The spheres repel and settle as shown. Calculate the initial Charge on...

I need to draw a single point charge with a magnitude of +4.3 C (coulomb's) I want to make sure that I am doing this right so: If one electron equals 1.602*10^-19 C than +4.3 C is actually a negative charge and therefore -4.3 C would be a positive charge. Is this right or do i have it...

Homework Statement A rod is bent into a semi circle of 180 degrees. The bottom half has a charge of -q and the top half a charge of q. Find the electric field at the center of the circle, point P. Homework Equations E = kq/r^2 The Attempt at a Solution I tried to set up an...

Homework Statement A small 2g plastic ball is suspended by a 20 cm long string in a uniform electric field. If the ball is in equilibrium when the string makes a 15 degree angle with the vertical as indicated, what is the net charge on the ball? Here's the diagram...

Homework Statement Two small metallic spheres, each of mass 0.2g are suspendedas pednulums by light strings from a common point. The spheres are given the same eletric charge, and it is found that they come to equilibrim when each stringis at an angle of 5degrees with the vertical. If each...

Homework Statement A point charge q = -0.80 nC is fixed at the origin. Where must a proton be placed in order for the electric force acting on the proton to be exactly opposite to its weight? (Let the y-axis be vertical and the x-axis be horizontal.) Homework Equations F=(kq1 q2)/r^2...

Homework Statement Five point charges on a straight line are separated by a distance of 0.01 m. For what values of q2 and q4 would the net force on each of the other three charges be zero? q1-----q2-----q3-----q4-----q5 Where: q1= 2x10^-6 C q3= 1x10^-6 C q5= 2x10^-6 C Homework...

Homework Statement Charges q1 and q2 exert repulsive forces of 15 N on each other. What is the repulsive force when their separation is increased so that their final separation is 160% of their initial separation? a.1.3 N b.9.8 N c.8.7 N d.5.9 N Homework...

Ahhh, just typed out a big long post and I did something wrong and now it's gone. Oh well. This problem was given on a practice problem sheet in my first year university physics class. Homework Statement You have a lightweight spring whose unstretched length is 4.0 cm. You're curious to...

Hello, I am new here. I have a question that I cannot seem to find an answer to and is beginning to bother me in the worst way. I was researching to find out how Coulomb developed the formula that is used today (since I do not have the programme, I shall not even attempt to write it) and found...

Homework Statement how to use coulomb's law to find the r value of the three points when the total distance is 50 cm Homework Equations f=Kqq/r^2 The Attempt at a Solution i assumed that is it was uniform and sais r1+r2=r3 but now i think that is wrong