Shell Definition and 750 Threads

Homework Statement Use the shell method to find the area of the resulting shape when the region bounded by y=4x-x2 and y=0 is rotated about the line x=5. Homework Equations 2π ∫ (shell radius)(shell height) dx (from x=a to b) The Attempt at a Solution I know the region I am...

Homework Statement What is the electric field if r=a and r=b? Reference:http://www.youtube.com/watch?v=BcuQ2c_WrMc" 2:11 And what if the net charge is just -Q on the conductor instead of -3Q? Will the electric field at r>b be 0? Reference: Same video, 3:00-3:10 Homework Equations...

Homework Statement A cylindrical distribution of charge [tex]\rho=\frac{\alpha}{\sqrt{r}}[\tex] where [ tex ]\alpha = \frac{2\muC}{m^\frac{5}{2}} [ \tex ] extends from 0 cm to 8.2 cm. Concentric with this is a dielectric shell with 4.08 of inner radius 16 cm and other radius 26 cm. What is...

Hello, Homework Statement My problem regards the disk|washer, and cylindrical shell methods for finding volumes in single variable calc. My problem is basically am I understanding these two methods and their relationships properly. Fundamentally, these methods are indentical, as we can...

Hi all I hav written a very small shell script in bin bash & its not working. The script is :: #!/bin/bash i=1.0 while [ $i -le 3.0 ] do i=`expr "$i + 0.5" | bc`; echo "i=$i" done The error is : line 6: [: 1.0: integer expression expected I think the use of decimals in the...

Homework Statement A right solid conducting cylinder has a total charge of +5.10 mC. Inside the cylinder a charge q = -1.55 mC rests at the center of a hollow sphere as shown in the diagram below. What is the charge on the surface of the hollow sphere? Homework Equations The Attempt at a...

Homework Statement Find the volume generated by rotating the given region about the given line using the Shell method and the Washer method. x = 4y [y = x/4], y = 0, x = 0, x = 8 about x Homework Equations Washer method (about x): V = pi \int^b_a ((Rtop2(x) - rbottom2(x))dx...

Homework Statement A cylindrical shell of radius 9.9 cm and length 286 cm has its charge density uniformly distributed on its surface. The electric field intensity at a point 23 cm radially outward from its axis (measured from the midpoint of the shell ) is 44800 N/C. Given: ke = 8.99 × 10^9...

Homework Statement Find the work done to move a test charge with charge q from the origin to the edge of a spherical conducting shell which surrounds it, also of charge q. (Shell is of radius R). Homework Equations W = int(F.ds) where W = work done, F = force The Attempt at...

Homework Statement A point charge +Q is surrounded by a spherical shell of inner radius a and outer radius b. The spherical shell has charge density \alphar. a) What is the electric field for r < a? b) What is the electric field for a < r < b? c) What is the electric field for r > b? d)...

Homework Statement Show that a conductive shell a<b has a resistance of R= (a-1-b-1)/(4πσ) Homework Equations J = σE I = JA = σEA R=(Va-Vb)/I The Attempt at a Solution My problem is my algebra i think. First i found the electric field Qenc= ρV =...

Homework Statement An infinite line of charge with linear density λ = 8.8 μC/m is positioned along the axis of a thick insulating shell of inner radius a = 2.9 cm and outer radius b = 4.1 cm. The insulating shell is uniformly charged with a volume density of ρ = -659 μC/m3. What is λ2, the...

Homework Statement Is the probability that an electron transitions from the N to M (n = 4 to n = 3) shell different than the electron going from L to K (n = 2 to n = 1)? So basically, should I expect to see a lot more transitions from n = 2 to n = 1, than any other type of transition? If...

Homework Statement A thick-walled, conducting spherical shell has charge q = +10 mC, inner radius R1 = 10cm, and outer radius R2 = 50 cm. A point charge Q = -20 mC is located at the center of the shell. Describe the the charge distribution in the shell. 2. Given answer +20 mC on...

Consider a charged spherical conducting shell. I understand that Gauss's law implies that there is no charge on the inside surface of the conducting shell. Now consider a charged spherical conducting shell with lots of holes cut uniformly all over it. Would Gauss's law still imply that...

The question: Use the shell-model diagram provided to justify the spins and parities of the ground-state of 39Ca, 40Ca, 41Ca and 41Sc. Give the spins and parities of the first excited state of 39Ca,41Ca and 41Sc (Z=20 for CA and Z=21 for Sc) My problem: Although I'm fairly certain I've got the...

There's no electric field inside a conductor, a classic observation of electrostatics. Any field that "should" exist is compensated for by charge redistribution on the surface of the conductor. This produces classic results like shielding since in a hollow conductive shell, the field is still...

Homework Statement http://www.catholiccentral.net/Document.Doc?id=200 problem number 5 Homework Equations 2pi intergral x(9x^4/625) The Attempt at a Solution When I do the shell method it doesn't give me the same answer as if I use disk. I've also noticed that when I do the...

Homework Statement Hey everyone, I'm studying for my physics and came across a question for the COM of a hemisphere. However, I was wondering what methods there are to find the COM of a hemispherical shell instead. Any insight would be very much appreciated! =) After much of tearing Google...

Hi all Suppose we have a conducting shell (which is not necessarily a sphere) and no electric charge inside. Is the electrostatic field inside the conducting shell always zero? (even if there is some charges outside the shell) What if the shell is grounded? If the answer is yes, how it...

Does anyone know how to even start this problem.. :( I seriously have no idea...spent like few hours to find this out on the library and no luck... Please help a poor guy out...I aint smart enough for this...

Homework Statement There's a conducting spherical shell with Q = q2 and V =100v and outter radius R Homework Equations V=k*Q/R The Attempt at a Solution First I calculate the E field using Gauss law, and I get E=q2/4*Pi*E0*r Integrating the E field to get the potential V y...

http://www.guardian.co.uk/business/2010/dec/08/wikileaks-cables-shell-nigeria-spying 70% of Nigerians who live below the poverty line will be none too happy to read about this.

Homework Statement The shell of a shotgun, after being fired, with a velocity of v=1000 m/s gets split into two parts with equal masses. One of the two parts continues to move on the same direction as the whole (not separated) shell did, with a velocity of v=1500 m/s. a) Find the velocity...

Homework Statement Region bounded by y=x^2 and y=3x. Set up integrals to determine volume of solid obtained by rotating the region about: 1. the x axis show both disk/washer method and shell method 2. the line x=4 show both disk/washer method and shell methodThe Attempt at a Solution I...

Benzene forms the electron shell configuration of two rings of electrons, parallel to the molecule, shown here http://upload.wikimedia.org/wikipedia/commons/thumb/9/90/Benzene_Orbitals.svg/750px-Benzene_Orbitals.svg.png so my question is, if an electron beam is run through the center of the...

Homework Statement A long, hollow conducting pipe of radius R and length L carries a uniform current I flowing around the pipe. Find expressions for the magnetic field (a) inside and (b) outside the pipe. Hint: What configuration does this pipe resemble? Homework Equations Ampere's Law...

Homework Statement A shell is shot with an initial velocity 0 of 23 m/s, at an angle of θ0 = 54° with the horizontal. At the top of the trajectory, the shell explodes into two fragments of equal mass (Fig. 9-42). One fragment, whose speed immediately after the explosion is zero, falls...

Getting bash shell script to do one thing if user hits "enter". I need to write a program that will output a line in a calendar file if a date is entered, or if no date is entered and the user just hits "enter" to ouput the line corresponding to today's date. I think that it must take the...

Hi all 30 students have sent me their answers to me in folders, "name1", "name2", ..., "name30". Each folder contains 2 outputs, "output_a.txt" and "output_b.txt" Now I have the correct answer "correct_a.txt" and "correct_b.txt" with me. I know that using the command diff, I can compare...

Dear reader, Of course I searched the site to see other persons discussing the the egg shell theory, but I did not find it. So, perhaps someone can direct me to the subject. I am interested in the theory that when the universe was created in a big bang, the only part of it is the part we...

Homework Statement A coastal defence cannon fires a shell horizontally from the top of a 50.0m high cliff directed out to sea with a velocity of 60.0m/s. Determine the range of the shell's trajectory.Homework Equations delta x = ut (horizontally) delta y = ut + 1/2 at^2 The Attempt at a...

Hi all I badly need some help... I plot a file output1.txt in the following way :: gnuplot> plot "output1.txt" using 1:2 with lines, \ plot "output1.txt" using 1:3 with lines BUT now I have many data files, output1.txt, output2.txt, output3.txt, ...,... ,output1000.txt I need to...

a cannon is placed on an edge of a cliff and launches shell with an initial velocity of 710m/s [35degrees above the horizontal]. the shell lands 15m below its launching position. a) determine the max height of the shell b) determine the horizontal range of the shell from the base of the cliff...

A shell of mass 0.4 kg is at rest in a gravity-free environment when it suddenly explodes into three fragments. The mass and x,y components of two of the fragments is given in the table:particle mass (kg) vx (m/s) vy (m/s) [1] 0.12 25 58 [2]...

Homework Statement A spherical shell of inner radius a and outer radius b contains a uniform charge density ρ of total charge Q. (a) Find ρ (b) find the electric field for r< a, a< r< b, b< r sketch it Homework Equations E = kQ/r2 V=4πr3 The Attempt at a Solution ρ π...

Homework Statement Use the shell method to set up and evaluate the integral that gives the volume of the solid generated by revolving the plane region about the y-axis. y=4x-x^{2} , y=4 , x=0 Homework Equations V=2\pi\int p(x)h(x) from a to b The Attempt at a Solution...

1. Find the electric potential inside and outside a uniformly charged sphere of radius R, and whose total charge is q. Use infinity as your reference point. Compute the gradient of V in each region and check that it yields the correct field. Sketch V(r). 2. I used the theorem that electric...

Homework Statement Calculate the electric field, E, for general points inside a shell which has a radius R. It also has a uniform surface charge density, σ. First, do it with Gauss’s Law. Then find E more directly. Hint: Use Law of Cosines and a substitution. Homework Equations...

Homework Statement Moment of inertia of spherical shell of radius R, mass M along its rotation axis is given by \frac{2}{3}MR^{2} I am trying to calculate thisHomework Equations The Attempt at a Solution This is my attempt but is unsuccessful, since the spherical shell is an assembly of rings...

Potential of Concentric Cylindrical Insulator and Conducting Shell...Please Help Homework Statement An infinitely long solid insulating cylinder of radius a = 3.6 cm is positioned with its symmetry axis along the z-axis as shown. The cylinder is uniformly charged with a charge density ρ =...

Homework Statement The area between the y-axis and the line y = x + 1 from y = 2 to y = 4 is rotated about the x-axis. Use the shell method to find the area of the resulting solid. Homework Equations V = 2pi integral (radius)(height of shell) dx or dy The Attempt at a...

Homework Statement 1. Homework Statement An infinite line of charge with linear density λ = 7.5 μC/m is positioned along the axis of a thick insulating shell of inner radius a = 2.9 cm and outer radius b = 4.9 cm. The insulating shell is uniformly charged with a volume density of ρ =...

Homework Statement An infinite line of charge with linear density λ = 7.5 μC/m is positioned along the axis of a thick insulating shell of inner radius a = 2.9 cm and outer radius b = 4.9 cm. The insulating shell is uniformly charged with a volume density of ρ = -612 μC/m3. What is λ2...

Homework Statement There is a Charged metal sphere with radius b placed inside the central of a ground metallic shell with a radius a. What will be the work done in bring a small positive charge q from infinity to the surface of the inner sphere? Homework Equations...

If a charge is placed inside a spherical conducting shell, is the total electric field inside it zero? I am thinking that if the charge is positive, then the conducting shell will have an equal amount of negative charge on its inner surface, therefore the E field should be zero inside, right?

i have a hemispherical shell with a radius of R ,and which has V=V0 potential on it. the main problem is i have to find the potential inside the shell for every (r,\theta,\phi) points. 1. I think the potential will depent on only the distance from origin, there won't be any \theta or \phi...

In quantum renormalization, one distinguishes between the (unobservable) bare electron and the observable properties. The justifications that I can find for the procedure seem to rest purely on mathematical and empirical grounds: the methods are in line with a consistent mathematical theory...

Let's suppose that we have two point particles with masses m1,m2 and the spherical shell with mass M, placed in a line, at distances h1,h2 and H from 0 in that line (0 is the center of some inertial frame of reference). The initial conditions and the equations of motion are the following...

Let's suppose that we have two point particles with masses m1,m2 and the spherical shell with mass M, placed in a line, at distances h1,h2 and H from 0 in that line (0 is the center of some inertial frame of reference). The initial conditions and the equations of motion are the following...