Point charges Definition and 349 Threads

Homework Statement There are three charges on the x-axis labled q1 = 9.9 uC, q2= -5.1 uC, q3 = ? The distance between q1 at the origin and q2 is 0.1 m, what is the equilibrium distance between q3 and q1, and does that distance depend on the polarity of q3 ? Homework Equations F =...

Identical 8-μc point charges are positioned on the x-axis at x=+/-1.0m and released from rest simultaneously. What is the kinetic energy of either of the charges after it has moved 2.0m? some relevant formulas are: E=kq/r^2 V=-Ed V=U/q my attempt at the question: i started by finding...

Three point charges with a distance a between them (as shown). What is the resultant force on q1? Is this correct or am I doing this completely wrong? edit: that should be Q1 multiplied by Q3 not adding http://img513.imageshack.us/img513/3668/untitledxr7.jpg

Homework Statement One particle has a mass of 3.00 10-3 kg and a charge of +7.50 µC. A second particle has a mass of 6.00 10-3 kg and the same charge. The two particles are initially held in place and then released. The particles fly apart, and when the separation between them is 0.100 m...

Two point charges are located on the x−axis: a charge of +7.80 nC at x = 0 and an unknown charge q at x = 0.50 m. No other charges are nearby. If the electric field is zero at the point x = 1.0 m, what is q? I separated the charges. q1 = +7.80 nC q2 = unknown I am confused about the...

Hey all this question appeared on my last assignment that was due on friday and had me completely stumped for the entire week and well still does, i couldn't even get off the ground (im not very good with these algebra questions) . anyway in the interests to doing my very best on my midterm exam...

Homework Statement Positive point charges q_1= 6.90 microC and q_2= 2.90 microC are moving relative to an observer at point P as shown in the figure. The distance from the observer to either charge is originally d = 0.190 m.The two charges are at the locations shown in the figure. Charge...

Hi, I'm currently taking first year physics in university and I have an online assignment due tonight. Due to it being saturday, I cannot contact any of the TAs or professors for help, and my friends and I are stumped. I had 15 tries at answering this question and now I only have 2 left...

Two point charges are separated by a distance r and repel each other with a force F. If their separation is reduced to 0.280 times the original value, what is the magnitude of the force of repulsion between them? I don't really understand this question and don't know where to start. Would...

What are the magnitude and direction of the electric field midway between two point charges, −14.0 µC and +13.0 µC, which are 7.40 cm apart? I used the F = ((k)(q1)(q2))/r^2 F= ((9x10^9)(-14)(13))/(7.40^2)) F= 2.99 x 10^10 however that answer is wrong. (The correct answer is...

For the life of me I can't seem to get this problem. An electrically neutral model airplane is flying in a horizontal circle in a 3m guideline, which is nearly parallel to the floor. The line breaks when the Kinetic energy is 50J. Now, reconsider the same situation, except now there is a point...

Homework Statement Two point charges lie on the x axis. A charge of +8.4 µC is at the origin, and a charge of -3.8 µC is at x = 10.0 cm. At what position x would a third charge q3 be in equilibrium? Homework Equations F=(kq1 q2)/r^2 The Attempt at a Solution I think that my main...

Hi, Homework Statement Two point charges 2.0 cm apart have an electric potential energy -149.9 µJ. The total charge is 28 nC. What are the two charges? Homework Equations U = (kqQ) / r The Attempt at a Solution U = -149.9 x 10^-6 = [(9 x 10^9)(28 x 10^-9 - q)(q)] / (0.02)...

"The net flux through ANY closed surface surrounding a point charge q is given by q/"permittivity of free space" and is independent of the shape of that surface." I'm having a little trouble understanding this... when my book derived this formula, it did so by using the surface area of a...

Hello, I am doing electrostatics at the moment and have difficulties to solve the following problem. Any hint that helps me to find the answer will be appreciated! "On every corner of a square are movable point charges with the charge of 'q'. Where does a fifth movable point charge have to...

I am having a little trouble knowing how to approach the following question: Twi point charges q and -q are placed 2d apart. Show that a conducting sphere of small radius r (where r << 2d) is placed midway between the charges, show the force on each is increased by a factor of approx (1 +...

Problem: A charge of +18 uC is on the y-axis at y = +3.0m. A charge of -12 uC is at the origin. Last, a charge of +45 uC is on the x-axis at x = +3.0m. Determine the magnitude and direction of the net electrostatic force on the charge at x = +3.0mm. Specify the direction relative to the...

I've been working on the following problem but when I try my answer online, it keeps coming up as incorrect. A charge Q1=-9.4 C is 4.8 m from a charge Q2 = 3.6 C. What is the magnitude of the electrostatic force on Q1? I'm pretty sure for this its just Coulomb's Law so: F = (k(Q1*Q2))/r^2 F...

Here is the problem: Three point charges are aligned along the x-axis as shown below. Find the electric field at the position x = +2.0m, y=0. ........y ........| --------|<--.50m --->|<--------------.80m-------->| --------0------------0-----------------------------0--------- X...

A point charge q is a distance d from a grounded conducting plate of infinite extent (figure a). For this configuration the potential V is zero, both at all points infinitely far from the particle in all directions and at all points on the conducting plate. Consider a set of coordinate axes with...

I'm working on the following problem: The drawing shows four point charges. The value of q is 2.0 µC, and the distance d is 0.74 m. Find the total potential at the location P. Assume that the potential of a point charge is zero at infinity...

Difficulties with dipoles & point charges... Help would be appreciated a lot with the following problems: ~ A positive point charge +Q is at the origin, and a dipole of moment p is a distance r away (r>>L) and in the radial direction as shown below...

suppose there existed 3 point charges with known charges and separating distances. I know you can determine the total potential of the system by using one charge as a reference (give it a potential of 0J), calculate the potential of another charge with respect to that charge (x J), and then...

A point charge q_1=-4.00\;{\rm nC} is at the point x = 0.600 m, y = 0.800 m, and a second point charge q_2=+6.00\;{\rm nC} is at the point x = 0.600 m, y = 0. Calculate the magnitude of the net electric field at the origin due to these two point charges.

Hello! Just hoping for a bit of help on a homework problem I'm doing at the moment... Basically this is the question: Three point charges are placed along the y axis: a charge q at y=a, a charge -2q at the origin and a charge q at q=-a. Such an arrangement is called an electric...

A point charge q =-4.00 nC is at the point x = 0.600 m, y = 0.800 m, and a second point charge q=6nC is at the point x = 0.600 m, y = 0. A)Calculate the magnitude of the net electric field at the origin due to these two point charges. I assume i can just treat the electric field charge...

A point charge q1 -4 nC is at the point x = 0.600 m, y = 0.800 m, and a second point charge q2 +6 nC is at the point x = 0.600 m, y = 0. I need to calculate the magnitude of the net electric field at the origin due to these two point charges. |...

How much voltage must be used to accerlerate a proton (radius 1.2E-15 m) so that it has sufficient energy to just penetrate a silicon nucleus? A silicon nucleus has a charge of +14e, and its radius is about 3.6E-15 m. Assume the potential is that for point charges.

Heres another similar question: Two point charges, q1= 0.50 x 10^-9 C and q2= 8.00 x 10^-9 C are seperayed by a distance of 1.20 m. At what point along the line joining the points charges, is the total electric field die to the two charges equal to zero?

Two positive point charges q are located on the y-axis at +-(1/2)s. Find an expression for the potential along the x-axis. Express your answer in terms of epsilon_0, pi, q, x, and s. for this one, i know V = (1/4*pi*epsilon_0)*q/r. so i was thinking its just like finding the potential of...

Three point charges are arranged at the corners of a square of side L. What is the potential at the fourth corner (point A), taking V = 0 at a great distance? OK, I am very confused. First of all, Giancoli (my textbook) seems to explain how to do this for one point charge, but I am confused...

Since the electron and the positron are indeed true "point charges" then why are the colliders able to make them collide head-on?

As shown below, an infinite number of point positive charges of 8.0 C are placed on the x-axis at x=a, 2a, 4a, 8a, ... with a=18 cm. Find the electric potential (in V) at the point x=0. 0---a----2a---4a-----8a------- Ok so I'm using the equation V=1/(4piEpsilon)Sigma(q/r). and it's not...

I've read that Dirac's equation for explaining spin does not hold if electrons are defined as true point charges. Is that correct?

The question and detail: I setup the problem using energy conservation: K_a + U_a = K_b + U_b: K_a = total kinetic energy of the 3 charges when they're at rest U_a = total potential energy of the 3 charges when they're at rest K_b = total kinetic energy of the 3 charges when they're far...

Given are two charges +1 X 10^-6 and one 3 X 10 ^ -6 distnace of 10 cm apart I know there is a poitn in between these two and it is 4 cm from the 1.0 X 10^-6 charge But i am asked to plot the elctric field strength as a function if the elctric field is pointing right, then positive...

http://eastvan.bc.ca/~kim/phys.jpg Four identical charges Q+ occupy the corners of a square with sides of length a. A fifth charge, q, can be placed at any desired location. Find the location of the fifth charge, and the value of q, such that the net electric force acting on the original...

I need help for the following problem: Two alpha-particles (diameter 1.9 x 10^-19 m) are headed directly toward each other with equal speeds. Compute the minimum energy in electron volts each particle must have if they are to collide. What inital speed must each particle have? For the...

An electron starts at the position (0,0) with an initial velocity 5,000,000 m/s at 45 degrees angle to the x axis. THe electric field is in the positive y direction and has a magnitude of 35000 N/C. At what location will the electron strikes? Please help me setup this problem. :confused:

A point charge of -.70microC is fixed to one corner of a square. An identical charge is fixed to the diagonally opposite corner. A point charge q is fixed to each of the remaining corners. The net force acting on either of the charges q is zero. Find the magnitude and algebraic sign of q...

Would the magnitude of the net electric force on a charge +Q in a case where there is another charge -Q a distance x away from +Q be equal to the force on +Q by -Q in a case where there is a neutral metal rod between them? (and same distance x away from each other) I would be inclined to say...

Five equal negative point charges (-q) are placed symmetrically around a circle of radius R. Calculate the electric field at the center of the circle. My Answer: Each one will be place 72 degrees from the other one (360/5), Each field line is directed toward the center (charges are...

Points A,B and C are at the corners of an equilateral triangle of side 3 metres. equal positive charges of 2 micro-Coulombs are at A and B respectively. What is the potential at C??

Three identical point charges, each of mass 140g and charge +q, hang from three strings. If the lengths of the left and right strings are each 10 cm, and each forms an angle of 48 degree with the vertical, determine the value of q.

Four point charges, each of magnitude 12.92 x 10^-6 C, are placed at the corners of a square 65.5 cm on a side. Given K_e = 8.98755 x 10^9 Nm^2/C^2. If three of the charges are positive and one is negative, find the magnitude of the force experienced by the negative charge. Answer in units of N...

*sigh*, Another long semester of physics... Anyways, here we go ! Here's the problem: Calculate the magnitude of the electric field at the center of a square with sides 27.3 cm long if the corners, taken in rotation, have charges of 1.10 microC, 2.20 microC, 3.30 microC, and 4.40 microC...

Problem 22. Two positive point charges, each of which has a charge of 1.9*10^-9C, are located at y=0.38m and y=-0.38m. a. Find the magnitude of the resultant electrial force on a charge of 1.8*10^-9 C located at x=0.28m. Answer in N. Note: I used a^2+b^2=c^2 to find r in Coluomb's law...

The electrostatic force between two point charges is 5.7*10^-4N. The charge on one of the point charges triples and the distant between the points doubles. What is the force between the two point charges?

I've been doing this question, but can't seem to get past a particular bit. here's the question: 'Two positive point charges Q are held on the x-axis at x = a and at x = -a. A third positive point charge q, of mass m, is placed on the x-axis away from the origin at coordinate x such that |x|...