Spheres Definition and 467 Threads

Homework Statement Calculate the force of electric repulsion between two small spheres placed 1.0 m apart if each has a deficit of 1.0 x 10^8 electrons. Homework Equations N = q/e qe = mg q = mg / e q = mgr / Vb e = 1.602 x 10^-19 C. k = 9 x 10^9 - not sure if relevant or not. Fe = qe...

Homework Statement For a hydrogen atom in a state with n=2 and l=0, calculate the probability of finding the electron between two spheres of radii r = 5.00a[SIZE="1"]0 and r = 5.01 a[SIZE="1"]0. Homework Equations As stated above, calculate the probability of finding the electron in...

Hello, I am trying to (numerically) solve the following reaction-diffusion equation for the probability density of the a pair, \rho (\vec{r}_1,\vec{r}_2): \dot{\rho} (\vec{r}_1,\vec{r}_2,t) = D_1 \nabla^2_1 \rho (\vec{r}_1,\vec{r}_2,t) + D_2 \nabla^2_2 \rho (\vec{r}_1,\vec{r}_2,t) - k...

Homework Statement There's three thick, conducting concentric spheres with radii R1, R2, R3 (R1 < R2 < R3) with charge Q1, Q2, Q3 respectively. a.- The middle one is now wired to the ground. Find its net charge b.- The internal and external spheres are now wired. Find the distribution of all...

Is it true that the surface of a (hyper)cube in Rn is homeomorphic to Sn-1? Or only for particular n?

Hi everyone. Take the open sets A=S^1 - N and B=S^1 - S, that is, the circle minus the north and south pole resp.. Noting that AnB=S^0 and that A and B are contractible, the Mayer-Vietoris sequence in reduced homology for this decomposition writes, \ldots \rightarrow...

It occurred to me that most unification theories propose at least 6 dimensions, and that the 6th dimension would look like a sphere or a doughnut. For the sake of greater simplicity, I will use a sphere for my question. My question is, if an object were traveling in the 6th dimension, would...

Homework Statement Three conducting spheres of radii a, b and c, respectively, are connected by negligibly thin conducting wires as shown in figure 4. Distances between spheres are much larger than their sizes. The electric field on the surface of the sphere of radius a is measured to be...

Homework Statement Two spherical shells have a common center. A -1.37 x 10-6 C charge is spread uniformly over the inner shell, which has a radius of 0.0422 m. A +5.86 x 10-6 C charge is spread uniformly over the outer shell, which has a radius of 1.60 m. Find the magnitude of the electric...

Homework Statement A total charge of 2.600 C is shared by two metallic spheres A (radius 7.00 cm) and B (radius 5.00 cm) that are connected by a thin wire of length 1.00 m. Find the charge on sphere A. (Note that the influence of sphere B is not negligible.) Homework Equations I...

Homework Statement A point charge is at the center of a conducting hollow sphere, with radius 0.011m, that is within another conducting hollow sphere of radius 0.041m. The point charge is Q0=+4.30e-6 C, the inner sphere has a net charge of Q1=-1.70e-6 C, and the outer sphere has a net charge...

Homework Statement Two 2.0-cm-diameter insulating spheres have a 6.50 cm space between them. One sphere is charged to + 89.0 nC, the other to - 95.0 nC. What is the electric field strength at the midpoint between the two spheres? Homework Equations Esphere = KQ/r^2 k = 8.99 * 10^9...

Homework Statement Suppose that the magnitude of the charge on the yellow sphere is determined to be 2q. Calculate the charge q_red on the red sphere. Express your answer in terms of q , d_1 , d_2 , theta and . Hi Guys iv done the first two bits to this problem the sign of the...

Homework Statement Initially, sphere A has a charge of –10e and sphere B has a charge of +20e. The spheres are made of conducting material and are identical in size. If the spheres then touch, what is the resulting charge on sphere A? a) +10e, b) -10e, c) -5e, d) +5e The attempt at a...

Homework Statement Styrofoam has a density of 300 kg/m3. What is the maximum mass that can hang without sinking from a 40-cm-diameter Styrofoam sphere in water? Assume the volume of the mass is negligible compared to that of the sphere. Homework Equations FB=poVog Volume of sphere...

Homework Statement 2 conducting spheres with radii 2 & 3m are connected with a conducting rod of thickness 0.1m & length 0.5m. 500C charge is put on the 2m radius sphere. Find the amount of charge on each sphere & on the rod. Homework Equations The Attempt at a Solution By...

Homework Statement A total charge Q is shared by two metal spheres of small radii R1 and R2, that are connected by a long thin wire of length L. Fin (a) the charge on each sphre and (b) the tension in the wire. Source: Haliday 4th edn chapter 26 q. 91, p. 738 The Attempt at a Solution...

Homework Statement A sphere of mass m1 traveling at velocity u1 collides elastically with a stationary sphere of m2. The particles move away with v1 and v2 respectively. I'm at part 4, of 5. It asks us to resolve the conservation of momentum equations normal and tangential to the...

Homework Statement I am trying to solve a question where I have three concentric metal shells at different radii. I am treating them as two capacitors in series. I would like to use the formula C= enot*area/distance between capacitors, but I have a few questions. Homework Equations...

Hi, I'd like to ask the good people of this forum for some help. Here's a problem I've been working on for a while, and I'm seriously at my wit's end. I guess there's something I'm missing here... Homework Statement Two insulating spheres have radii r[SIZE="1"]1 and r[SIZE="1"]2, masses...

Hi, I'd like to ask the good people of this forum for some help. Here's a problem I've been working on for a while, and I'm seriously at my wit's end. I guess there's something I'm missing here... Homework Statement Two insulating spheres have radii r[SIZE="1"]1 and r[SIZE="1"]2, masses...

Hi ... how can I calculate the force between two permanent magnetized spheres(each r in radius) and has a magnetization (M) when they are magnetically stuck together with unlike poles touching?? I tried to think about it and found the following: 1) I can treat it like Earth magnetic field...

Two small metal spheres are located 3.0 m apart. One has radius 0.48 cm and carries charge 0.15 uC. The other has radius 0.95 cm and carries charge 0.090 uC. If the two spheres were suddenly connected by a thin wire, how much charge would move along it? This is a question that I have been...

Homework Statement Consider a metal sphere and spherical shells. The innermost one is solid with radius R_1. A spherical shell surrounds the sphere and has an inner radius R_2 and an outer radius R_3. The sphere and shell are again surrounded by a shell of inner radius R_4 and outer radius...

Hey everyone, I have this question that does not make much sens to me and I can't find any clue on the internet. Find the shortest possible periode of revolution of two identical gratitating solid spheres which are in circular orbit in free space about a point midway between them. (You can...

There is a picture for this question so I will try to describe it to my best ability. Two small spheres, each with mass m=3g and charge q, are suspended from a point by threads of length L=.22m. What is the charge on each sphere if the threads make an angle of 15 degrees with the vertical...

Homework Statement Two nonconducting spheres, of r1=3.0cm and r2=2.0cm, are placed of an x-axis. They have surface charge densities of +6.0mC/m2 and +4.0 mC/m2, respectively, on their outside surfaces. The center of sphere r1 is on the origin and the center of sphere r2 is 10 cm away. What is...

The problem: Find the potential between 2 concentric spheres, of radii a & b, where the potential of the spheres are held at Ca*P3(cos(t)) & Cb*P5(cos(t)), where P3 & P5 are the 3rd & 5th Legendre functions, t is theta & Ca & Cb are constants. The general solution to Laplace with azimuthal...

Question on Proportionate spheres (Help!) A spherical balloon is partially blown up and its surface area is measured. More air is then added, increasing the volume of the balloon. If the surface area of the balloon expands by a factor of 9.4 during this procedure, by what factor does the radius...

Six circles fit tightly around one all of equal length, 12 spheres fit tightly around one sphere all of equal diameter. How many circles can fit around one which is 6 times the other circles diameter? How many spheres can fit around one sphere which is 6 times the diameter of the others?

Does the electromagnetic or acoustic resonant frequency of a hallow spherical object ever equal the circumference of that object? If not what are the formulas to calculate this? Thanks in advance.

We have two thin concentric conducting spheres r1 and r2. THe spheres are connected with a power source which supplies emf of epsilon_0. The smaller sphere is connected to the positive pole of the power supply and the larger sphere is connected to the negative pole. Using Gauss Law find the...

I want to calculate the capacitance of a system consisting a parallel plate and dielectric spheres of different radius and dielectric strength in between the plates. please give some mathematical derivation. I really need to know it,my career depends on it. Please help me. :) thanks &...

Homework Statement Two uniform solid spheres of mass M and radius R0 are connected by a thin (massless) rod of length 1.6R0 so that the centers are 3.6R0 apart. (a) Determine the moment of inertia of this system about an axis perpendicular to the rod at its center...

Homework Statement Two identical conducting small spheres are placed with their centers 0.300m apart. One is given a charge of 12.0 nC and the other a charge of -18.0 nC. a) Find the electric force exerted by one sphere on the other. b) Next, the spheres are connected by a conducting wire...

Two spheres are released from rest when the distance between their centers is 12R. Sphere 1 has mass M and radii R while sphere 2 has mass 2M and radii 3R. How fast will each sphere be moving when they collide? Assume that the two spheres interact only with each other. (Use G for gravitational...

Two unequally sized metal spheres are each charged. A wire is connected from one sphere to the other. When the wire is removed, the spheres will have the same potential. T/F? The answer is true (I looked up the key), but I do not understand why. I know that the spheres, due to being...

Homework Statement Four 7.5kg spheres are located at the corners of a square of side 0.70 m. Calculate the magnitude of the gravitational force exerted on one sphere which is in left and down corner of the square by the other three. Homework Equations F_tot = F_2 + sqrt(2) * F1 The...

Homework Statement Two small insulating spheres with radius 5.50×10−2 m are separated by a large center-to-center distance of 0.510 m. One sphere is negatively charged, with net charge -2.20 \mu C, and the other sphere is positively charged, with net charge 4.05 \mu C. The charge is...

Homework Statement Two nonconducting spheres have a total charge of 13.4 μC. When placed 0.362 m apart. the force of repulsion is 2.777 N. What is the value of the greater charge (Give your answer in coulombs)? Homework Equations The Attempt at a Solution

Homework Statement two thin conducting spheres, one inside the other. They are both centered about the same point. The outer sphere has a total charge Q and radius R2 and the inner sphere has a total charge -Q and radius R1. The magnitude of the charges is Q = 500 nC, and the radii are R1 =...

Dear all, Two hollow conducting spheres have a common center O. The dimensions of the spheres are as shown (attached above). A charge of −200 nC is placed on the inner conductor and a charge of +80 nC is placed on the outer conductor. The inner and outer surfaces of the spheres are...

Dose anyone know the relationship of cube root numbers and the fraction of 1/8 "Assuming a body of a size represented by X has a pitch of 1024 per second, then a pitch of 2048 (double 1024) per second will be produced by a body having a volume of some mean between 1/8 of X and the cube root of...

Two concentric spherical surfaces with radii R1 , R2 each carry a total charge Q. What is the electric field between the two shells? I don't know what kind of answer they are expecting. Do I just describe it? Here's my attempt: The field lines from the inner shell will point away from...

[SOLVED] Charged Spheres Homework Statement Two small aluminum spheres, each of mass 0.0250 kilograms, are separated by 80.0 centimeters. How many electrons would have to be removed from one sphere and added to the other to cause an attractive force between the spheres of magnitude 1.00x10^4...

or are they 1/8 of a sphere at the corners and 1/4 of a sphere at the edge?

Hi! Can someone illuminate why there are gravitational tendency in larger scale to form disks (galaxies, solar systems, accretion disks) whereas all smaller scale bodies (planets etc.) are spherical? What about the spherical halos in the galaxies, is just "unorganized matter" which will...

1. A sphere of mass m impinges obliquely on a sphere of mass M, which is at rest. The coefficient of restitution between the spheres is e. Show that if m=eM, the directions of motion after impact are at right angles 2. Coefficient of restitution - 3. I really don't think I have a...

Homework Statement At the point of fission, a nucleus of 235U with 92 protons is divided into two smaller spheres, each with 46 protons and a radius of 5.9x10^-15m. What is the repulsive force pushing these two spheres apart? Homework Equations F = k(qi)(q2)/d^2 The Attempt at a...

So I'm completely lost...here's the problem. There's a small ball inside an empty sphere. How can I prove this sphere doesn't attract the small ball gravitationally, independently of the position of the ball inside the sphere?? Also, how can I use the result from above to find the gravity...