Calculus 3 Triple Integration in Spherical Coords

Click For Summary
SUMMARY

The discussion focuses on evaluating the triple integral of z dV using spherical coordinates for the solid Q, which lies between the spheres defined by x²+y²+z²=1 and x²+y²+z²=4. The correct boundaries for the integral are established as 0 to 2π for θ, 0 to π for φ, and 1 to 2 for ρ. The participant initially arrives at a final answer of zero, which is explained as a result of the symmetry in the function z over the volume, leading to cancellation of positive and negative contributions. The conclusion emphasizes the importance of understanding the conceptual meaning of triple integrals in relation to the geometry of the problem.

PREREQUISITES
  • Understanding of spherical coordinates in calculus
  • Familiarity with triple integrals and their applications
  • Knowledge of volume integrals and symmetry in functions
  • Basic skills in evaluating integrals in multiple dimensions
NEXT STEPS
  • Study the properties of triple integrals in spherical coordinates
  • Learn about the geometric interpretation of integrals over symmetric regions
  • Explore examples of triple integrals with non-symmetric functions
  • Review the derivation and application of Jacobians in coordinate transformations
USEFUL FOR

Students and educators in calculus, particularly those studying multivariable calculus and triple integrals, as well as anyone seeking to deepen their understanding of spherical coordinates and their applications in evaluating integrals.

Wargy
Messages
3
Reaction score
0

Homework Statement



Use spherical coordinates to evaluate the triple integral z dV where Q is the solid that lies between x^2+y^2+z^2=1 and x^2+y^2+z^2=4.

Homework Equations


Not sure what goes here :P

The Attempt at a Solution


I've gotten everything set up, I am having problems with boundaries I think. Currently I am using 0 to 2\pi for \vartheta, 0 to \pi for \varphi and 1 to 2 for \rho. When solving, I get zero as my final answer, and since I'm not clear on the conceptual meaning of a triple integral that isn't of a function that equals 1 (volume) I don't know if this answer makes sense.
 
Last edited:
Physics news on Phys.org
It is zero. It's the integral of z on the volume between two spheres centered on the origin. It's as much positive as negative. The two cancel. But you should be using rho from 1 to 2.
 
Nevermind, read what you wrote again.
Thanks for the quick reply!
 
Last edited:
Makes a lot of sense.
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 21 ·
Replies
21
Views
3K
  • · Replies 9 ·
Replies
9
Views
1K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
2
Views
2K
Replies
3
Views
2K