Need suggestion on an MIT OCW material

AI Thread Summary
The discussion centers on a query regarding the upper limit of integration over "r" being infinity in MIT's course material on electric fields. The original poster mistakenly referenced the wrong page, while another participant clarified that the relevant page is likely page 63, where the total charge is calculated. The need for an infinite limit arises because the charge distribution extends infinitely in all directions. Additionally, there was a technical issue with the link provided, which was corrected. The thread was also moved to the appropriate section for better visibility.
kamaljit
Messages
4
Reaction score
0
Hi i would be glad if someone can help me on this.
I am having a bit of trouble in understanding why the upper limit of integration over "r" is infinity in the MIT open course material on Electric field page #16 by Prof Markus Zahn (material attached as a link to the pdf). Please help.

Thanks in advance.
Link to MIT oc material:
http://ocw.mit.edu/resources/res-6-002-electromagnetic-field-theory-a-probl%20em-solving-approach-spring-2008/textbook-contents/chapter2.pdf
 
Last edited by a moderator:
Physics news on Phys.org
Almost impossible to know what you mean when the link doesn't work and page 16 doesn't have any integral in it at all.

I'm guessing you perhaps meant page page 63 where he integrate to get the total charge? In that case the charge distribution extends to infinity (in all directions) so to get the total charge you need to integrate over the entire volume (i.e. infinity).

I also suspect your thread is posted in the wrong section.
 
  • Like
Likes kamaljit
Thank you for your quick reply and sorry that 1. the link isn't working (i copied the link correctly but somehow it is not working) and 2. about posting in the wrong section...
 
You got a space in "pro blem" in your link. This should be the correct one
http://ocw.mit.edu/resources/res-6-002-electromagnetic-field-theory-a-problem-solving-approach-spring-2008/textbook-contents/chapter2.pdf
I didn't spot it either at first but I found the course on ocw site.
 
Last edited by a moderator:
  • Like
Likes kamaljit
thank you for this correction.
 
Incand said:
I also suspect your thread is posted in the wrong section.

I've moved it. Cheers!
 
  • Like
Likes kamaljit
Thread 'Gauss' law seems to imply instantaneous electric field propagation'

Thread 'Gauss' law seems to imply instantaneous electric field propagation'

Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
View full post »

Thread 'Simple thought experiment with Stefan-Boltzmann law: energy'

Dear all, in an encounter of an infamous claim by Gerlich and Tscheuschner that the Greenhouse effect is inconsistent with the 2nd law of thermodynamics I came to a simple thought experiment which I wanted to share with you to check my understanding and brush up my knowledge. The thought experiment I tried to calculate through is as follows. I have a sphere (1) with radius ##r##, acting like a black body at a temperature of exactly ##T_1 = 500 K##. With Stefan-Boltzmann you can calculate...
View full post »
Thread 'A scenario of non-uniform circular motion'

Thread 'A scenario of non-uniform circular motion'

(All the needed diagrams are posted below) My friend came up with the following scenario. Imagine a fixed point and a perfectly rigid rod of a certain length extending radially outwards from this fixed point(it is attached to the fixed point). To the free end of the fixed rod, an object is present and it is capable of changing it's speed(by thruster say or any convenient method. And ignore any resistance). It starts with a certain speed but say it's speed continuously increases as it goes...
View full post »

Similar threads

Two networks described by v-i graph: Find voltages when interconnected
Replies
1
Views
1K
Thermodynamics question (Adiabatic expansion)
Replies
1
Views
7K
Suggestion for a good book on Riemann Surfaces - your personal experiences
Replies
5
Views
6K
Mathematica This Week's Finds in Mathematical Physics (Week 266)
Replies
1
Views
3K

Hot Threads

Recent Insights

Back
Top