Spherical Definition and 1000 Threads

  1. W

    Potential difference inside a spherical shell

    Homework Statement A top half of a spherical shell has radius R and uniform charge density sigma. Find the potential difference V(b)-V(a) between point b at the north pole, and point a at the center of the sphere. Homework Equations The Attempt at a Solution \oint E ds =...
  2. H

    Parametric Representation in Spherical and Cartesian coordinates

    Give a parametric representation of the following surfaces in terms of the given parameter variables: a) The first octant portion of the sphere (x^2) + (y^2) + (z^2) = 16 in terms of the spherical variables theta and phi. b)The graph of the function z = (x^3) - sqrt(y) in terms of the...
  3. L

    Gauss Law Problem With A Spherical Conductive Shell

    You are a hollow metallic sphere of inner radius r1, and outer radius r2. Inside is a charge of magnitude Q and a distance d<r1 from the centre. First I need to draw the electric field lines for regions r<r1, r1<r<r2, and r2<r Since the sphere is a conductor the only place where there is...
  4. X

    What is the Correct Calculation for Spherical Aberrations in a Lens?

    Homework Statement A collimated light beam is incident on the plane side of a of index 1.5, diameter 50mm, and radius 40mm. Find the .Homework Equations Refraction in a plane surface: s'=\frac{-n_2}{n_1}s Refraction on a spherical surface: \frac{n_1}{s}+\frac{n_2}{s'}=\frac{n_2-n_1}{R}...
  5. J

    Quick question with spherical coordinates and vectors

    So here's the question: An ant crawls on the surface of a ball of radius b in such a manner that the ants motion is given in spherical coordinates by the equations: r = b, \phi = \omegat and \vartheta = \pi / 2 [1 + \frac{1}{4} cos (4\omegat). Find the speed as a function at time t and the...
  6. V

    Trying to derive equation for acceleration in spherical coordinate system

    Homework Statement I was trying to figure out how to derive acceleration in spherical coordinates, and I realized that I need to find the projection of each spherical unit vector [ e(r), e(θ), and e(φ)] onto each Cartesian unit vector [î, j, and k], but I'm not quite sure as to how to do that...
  7. J

    Electric Potential Energy Spherical Shells

    Homework Statement A solid sphere of radius R has a uniform charge density ρ and total charge Q. Derive an expression for its total electric potential energy. Suggestion: Imagine that the sphere is constructed by adding successive layers of concentric shells of charge dq = (4\pi r^{2} dr) ρ...
  8. B

    Dot product in spherical coordinates

    Homework Statement What is the dot product of two unit vectors in spherical coordinates?Homework Equations A∙B = ||A|| ||B|| cos(\theta) = cos(\theta)The Attempt at a Solution The above equation is the only relevant form of the dot product in terms of the angle \theta that I can find. However...
  9. D

    Expressing a potential inside a spherical shell as

    Homework Statement The potential inside a spherical shell is given by: V_{-}(x,y,z)= \frac{V_0}{R^2}(6z^2-3x^2-3y^2) P_n(\cos(\theta )) where \theta is the polar angle. The potential on the surface carries a surface charge density \sigma. Besides this, ther's no other charges and no outher...
  10. D

    Potential inside NON-Conducting hollow spherical shell

    Hi Guys, Suppose we have a spherical shell with charge density on the surface \sigma and radius R. The potential inside the shell is given by: V_(x,y,z) = \frac{V0}{R^{2}}(6z^2+ax^2+by^2) It is assumed, that the potential is rotational symmetric around the z-axis inside and outside the...
  11. J

    Forgotten my maths Simple 1D ODE, spherical coordinates

    Hi, I seem to have forgotten some of my math how-to, as I haven't done this in a while. Looking through my notes, Bird, Stewart and Lightfoot, Greenberg, etc. don't really help. My equation is this, at steady state: 0 = 1/r^2 ∂/∂r (D*r^2 ∂C/∂r) + P Where P is some production rate...
  12. B

    Angles within a spherical triangle

    Hi Guys, need some assistance. I am sure what I am asking is trivial but i still need help. How could i find the angle within a spherical triangle (triangle formed on a sphere). Now this triangle has equal lengths on all 3 sides. Pleas help!
  13. F

    What, Physically is a Spherical Harmonic?

    What, "Physically" is a Spherical Harmonic? I'm trying to use spherical harmonics to get an equation to fit a set of data I have. I'm fine with that, I've found a derivation of what the general form is and I crunch that into MATLAB. My problem is derivations online really don't help me...
  14. P

    Charge Distribution on Conducting Spherical Shell

    Homework Statement A conducting spherical shell that has zero net charge has an inner radius R1 and an outer radius R2. A postive point charge q is placed at the center of the cell. The 1st part was to find the electric fields at the 3 diff places. The part I need help on is where we have to...
  15. Y

    Expressing a Field in Spherical Coordinates as Cartesian Vectors

    Homework Statement A field is given in spherical coordinates as F=[cos(θ)/r2]∙ar+[sin(θ)/r]∙aθ. Express F in terms of x, y, z, ax, ay, azHomework Equations ar∙ax=sin(θ)cos(∅) ar∙ay=sin(θ)sin(∅) ar∙az=cos(θ) aθ∙ax=cos(θ)cos(∅) aθ∙ay=cos(θ)sin(∅) aθ∙az=-sin(θ) x=r*sin(θ)*cos(∅)...
  16. L

    The influenza A virus is a spherical virus

    1. Homework Statement [/b] A typical virus is a packet of protein and DNA (or RNA) and can be spherical in shape. The influenza A virus is a spherical virus that has a diameter of 85 nm. If the volume of saliva coughed onto you by your friend with the flu is 0.044 cm3 and 10−9 of that volume...
  17. D

    Spherical Harmonic Wave Function =? 3D Wave Function

    Homework Statement Prove that the spherical harmonic wave function \frac{1}{r}e^{i(kr-{\omega}t)} is a solution of the three-dimensional wave equation, where r = (x^2+y^2+z^2)^{\frac{1}{2}} . The proof is easier if spherical coordinates are used. Homework Equations Wave function...
  18. S

    Electric potential, spherical conductor

    Hello, in this diagram, the shaded regions are spherical conductors. What's the potential at A=B? Ignoring the outer sphere, it should be kQ/R. When you add the outer sphere, potential at C=D=0 and electric field between B and C is kQ/x^2 so i integrated (kQ/x^2) dx with interval [2R, R]...
  19. Y

    Any grapth utility program that can plot graph with spherical coordinates?

    I want to study antenna patterns of different arrangements. I am looking for a very cheap software ( free is even better) to plot graph if I provide the \;R,\theta,\phi. Even if 2D plot would be helpful like keeping either \;\theta\;\hbox { or }\; \phi\; constant and vary the other angle to...
  20. S

    Dirac particle in a spherical potential box

    Hello, I'm studyng relativistic quantum mechanics by the book Relativistic quantum mechanics. Wave equations - Greiner, W. and I'm trying to derive the energy eingenvalues for s1/2 states, so I have the equation that I uploaded with the name eq1.jpg. In the text the author says, "If we assume R0...
  21. H

    Why Does Charge Flow to Outer Spherical Shell?

    So there are two concentric conducting spherical shells one with radius R and another 2R with charge +Q and +2Q respectively... Now the two are connected by a conducting wire. Why does the entire charge flow to the outer shell? Please clarify my doubts. I will be grateful.
  22. I

    Divergence in spherical polar coordinates

    I took the divergence of the function 1/r2\widehat{r} in spherical coordinate system and immediately got the answer as zero, but when I do it in cartesian coordiantes I get the answer as 5/r3. for \widehat{r} I used (xi+yj+zk)/(x2+y2+z2)1/2 what am i missing?
  23. 2

    Curl in spherical polar coordinates

    Hey, I've been stuck on this question for quite a while now: Homework Statement 1a. Write down an expression for the position vector r in spherical polar coordinates. 1b. Show that for any function g(r) of r only, where r = |r|, the result \nabla x [g(r)r] = 0 is true. Why does this...
  24. R

    The spherical symmetry of massive bodies

    Homework Statement Consider the study of the motion of a two bodies system interacting with only gravitational forces. If the two bodies (or even one of them) has not spherical symmetry, how will you proceed? Indeed the Earth and the moon does not have spherical symmetry mass distributions...
  25. R

    Concave Spherical Mirrors: Object Position for Inverted and Enlarged Image?

    Homework Statement A concave spherical mirror has a radius of curvature of magnitude 27.1 cm. Determine the object position for which the resulting image is inverted and larger than the object by a factor of 4.00. Homework Equations Mirror equation in terms of focal length: 1/p + 1/q =...
  26. R

    Spherical mirror radius of curvature

    Homework Statement A dentist uses a spherical mirror to examine a tooth. The tooth is 1.13 cm in front of the mirror, and the image is formed 10.8 cm behind the mirror. Determine the mirror's radius of curvature. Homework Equations 1/p+1/q=1/f f=R/2 The Attempt at a Solution...
  27. I

    Problem about spherical angle operators

    Hi Here's the problem I am trying to do. a) Is the state \psi (\theta ,\phi)=e^{-3\imath \;\phi} \cos \theta an eigenfunction of \hat{A_{\phi}}=\partial / \partial \phi or of \hat{B_{\theta}}=\partial / \partial \theta ? b) Are \hat{A_{\phi}} \;\mbox{and} \;\hat{B_{\theta}}...
  28. A

    Theoretical Rotational-Linear Kinetic Energy Ratio of Spherical Projectile

    For my investigation regarding the aerodynamic forces on a spherical projectile, I really need to know the theoretical ratio of rotational kinetic energy to linear kinetic energy of a spherical projectile (assuming the only spin is forward spin and there is no Magnus effect). Can someone please...
  29. D

    Triple integral w/ spherical subsitution

    Homework Statement f(x) is a differentiable function let F(t)= \int\int\int_{x^2+y^2+z^2\leq t^2} f(x^2+y^2+z^2) dx dy dz compute F^{'}(t) Homework Equations x=p sin \phi cos\theta y= p sin \phi sin\theta z= p cos \phi spherical bounds 0<p<t 0<\phi<\Pi 0<\theta < 2\Pi p^2...
  30. M

    Deriving Sphere Volume using Spherical Coordinates: Why 0°-360°?

    I wanted to derive the volume of a sphere using triple integration with spherical coordinates, but instead of taking the limits of θ as (0° ≤ θ ≤ 180°), I chose to take (0° ≤ θ ≤ 360°), and therefore, for φ as (0° ≤ φ < 180°), Now of course the integral of sin(θ) from 0° to 360° is zero, and...
  31. W

    Multivariable calculus, Integral using spherical coordinates

    Homework Statement Using spherical coordinates, set up but DO NOT EVALUATE the triple integral of f(x,y,z) = x(x^2+y^2+z^2)^(-3/2) over the ball x^2 + y^2 + z^2 ≤ 16 where 2 ≤ z. Homework Equations x = ρ sin ϕ cos θ y = ρ sin ϕ sin θ z = ρ cos ϕ ρ^2 = x^2 + y^2 + z^2 ∫∫∫w...
  32. N

    Spherical Vector Addition Process

    Hello Everyone, I was just wondering if there was a way to add two vectors that are determined by spherical coordinates (radius, theta, phi). For example, if I have v1 = (5, Pi/4, Pi/2) and v2 = (3, Pi, -Pi/2) is there a way to add these using their respective radii, thetas, and phis or do I...
  33. C

    Derivation of the moment of inertia eqn for a thin spherical shell

    So I've been trying to derive the moment of inertia equation for a thin spherical shell and I've slammed into a dead end algebraically. I was able to derive an equation for a hollow sphere: I = (2/5) M (Ro^5 - Ri^5)/(Ro^3 - Ri^3) where Ro is the distance to the very outside of the sphere...
  34. X

    Polarization Charge on the surface of a spherical cavity

    Homework Statement The polarizatiob charge on the surface of a spherical capacitor is -\sigma_e \cos(\theta), at a point whose radius vector from the centre makes an angle \theta witha given axis Oz. Prove that the field strength at the centre is \frac{\sigma_e}{3 \epsilon_0}, Homework...
  35. 1

    Related rates and a spherical weather balloon

    (b]1. Homework Statement [/b] A spherical weather balloon has a radius of 1m when it is 1500m high. You observe that the radius increases at a rate of 2cm/min as it continues to rise. At what rate is the surface area increasing when the radius is 4m? Homework Equations I thought...
  36. C

    Steady state heat equation in concentric spherical shells

    Homework Statement Homework Equations The Attempt at a Solution I'm trying to find the steady state solution to the heat equation for a system of spherical shells (looks like http://correlatingcancer.com/wp-content/uploads/2009/01/nanoshell-thumb.jpg" ) where heat generation Q occurs in...
  37. N

    Triple integral in spherical form

    consider this following triple integral 1/(x^2+y^2+z^2)dxdydz bounded above by sphere z=(9-x^2-y^2)^1/2 and below by the cone z=(x^2+y^2)^1/2 what i have done: z=Pcospi P^2=x^2+y^2+z^2 9=x^2+y^2+z^2 P=0 to 3 pi=0 to pi/4 theta=0 to 2pi is this the correct range?
  38. Y

    Electric field in a spherical shell

    Homework Statement A -5-nC point charge is located at the center of a conducting spherical shell. The shell has an inner radius of 2 m, an outer radius of 4 m, and a charge of +7 nC. (Let the radially outward direction be positive.) (a) What is the electric field at r = 1 m? (Indicate the...
  39. Q

    Questions about EM properties of ferrous liquids in spherical form

    I am an ameteur physicist (i actually have my degree in meteorology), and i have some questions about the EM properties of liquid metals or ferrous liquids when in spherical form. I understand if you are too busy or if i sound off, but if you do have the time to answer a few questions, it would...
  40. C

    Learning Spherical Harmonics & Angular Momentum

    Homework Statement I want to understand spherical harmonics. I want to really grok them deeply. I want to be able to visualize them and understand them. I'm the sort who can't take anything on faith, especially where quantum mechanics is concerned. So I want to understand angular...
  41. L

    Spherical capacitor with 2 dielectrics.

    Homework Statement The problem is on page 40 of this PDF: http://web.mit.edu/8.02t/www/802TEAL3D/visualizations/coursenotes/modules/guide05.pdf Find the capacitance of a spherical capacitor with 2 different homogeneous dielectrics arranged concentrically.The Attempt at a Solution In that...
  42. T

    Calculating Electric Field of Spherical Charge Distribution

    Homework Statement Compute the electric field generated by a spherically symmetric charged sphere of radius R with charge density of \rho = kr^{2} Homework Equations \oint _S \vec{E} \cdot \vec{dA} = \frac{Q_{enclosed}}{\epsilon_0} The Attempt at a Solution I know that this question...
  43. C

    Can You Recall the Formula for Finding the Area of a Spherical Patch?

    Does anyone remember the formula for the area of a spherical patch in terms of two angles? Obviously you parametrize the surface and do the surface integral but I'm a bit too lazy/busy right now. So does anyone just remember the result? By spherical patch I mean something like this: I want...
  44. D

    Spherical Trigonometry question

    Im trying to use spherical trig to solve a problem In the standard method to compute the angles, I already have only the following four angles A, a, B, b but from these, how can I compute either C, or c? Thanks
  45. Y

    Clarification on curl and divergence in cylindrical and spherical coordinates.

    Divergence and Curl in cylindrical and spherical co are: \nabla \cdot \vec E \;=\; \frac 1 r \frac {\partial r E_r}{\partial r} + \frac 1 r \frac {\partial E_{\phi}}{\partial \phi} + \frac {\partial E_z}{\partial z} \;=\; \frac 1 {R^2} \frac {\partial R^2 E_R}{\partial R} + \frac 1 {R\;sin...
  46. D

    Poission equation, spherical harmonics, looking for reference

    Hi folks, I'm looking for a derivation of the following statement (formula 76) http://img845.imageshack.us/img845/1550/screenshot4op.png Do you know any reference, where I can find a bit more detailed description? I reckon, you can find it in Jackson's electrodynamic book, but I couldn't find...
  47. S

    Spherical electric field of electron.

    On May 25, 2011, the journal Nature published an article stating that the electron was experimentally found to be extremely spherical. In Volume II, Chapter 5 of Feynman's Lectures on Physics, he states that the electric field of an electron has been experimentally determined to vary...
  48. B

    Spherical Harmonic Hydrogen Wavefunction

    Homework Statement Give a physical explanation of why a spherically symmetric Ylm cannot describe the state of a system with non-zero angular momentum. Homework Equations The Attempt at a Solution I was thinking that if Ylm is spherically symmetric then the particle is equally...
  49. O

    Spherical aberration in high NA objectives

    hi everybody, i would appreciate it if someone could clarify the concept of spherical aberrations in the context of high NA objectives in which use lenses are used that are not exclusively of the spherical type. a common thing that you hear is that some objective is corrected for 0.17mm...
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