Magnetic Field due to rotating disks

Click For Summary
The discussion centers on the magnetic field generated by two identical rotating disks with the same angular velocity about the z-axis. The fields from the disks will not completely cancel or double at all points unless they are superposed. At specific points, the fields may either cancel or reinforce each other. The right-hand rule can be applied to find the direction of the magnetic fields, and the superposition principle helps in analyzing their combined effect. Understanding the charge density and configuration of the disks is crucial for accurate calculations.
E&M
Messages
35
Reaction score
0

Homework Statement


There are two rotating disks which rotate with angular velocity omega in the same direction about a z axis. Will the magnetic field at the center of those two disks cancel out or will it be twice the field due to one of the disks? This is a part of a bigger problem. So, I haven't posted the relevant equations and attempt as I have already figured out other things. Thanks in advance.


Homework Equations





The Attempt at a Solution

 
Physics news on Phys.org
What field point(s) is this question in regard to? Unless the two disks are superposed, the fields will neither completely cancel or double at all field points. However, there are some points at which one of those will happen.

Are the disks identical (do they carry the same charge density?)? Assuming the question is about a point on the z-axis, you can use the right hand rule to determine the direction of each constituent field and then use the superposition principle to determine whether they cancel or double.
 
(a) The polarisation pattern is elliptical with maximum (1,1) and minimum (-1,-1), and anticlockwise in direction. (b) I know the solution is a quarter-wave plate oriented π/4, and half-wave plate at π/16, but don't understand how to reach there. I've obtained the polarisation vector (cos π/8, isin π/8) so far. I can't find much online guidance or textbook material working through this topic, so I'd appreciate any help I can get. Also, if anyone could let me know where I can get more...

Similar threads

  • · Replies 7 ·
Replies
7
Views
2K
Replies
11
Views
2K
  • · Replies 1 ·
Replies
1
Views
581
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
15K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 5 ·
Replies
5
Views
504