Static electricity with spinning disks

Click For Summary

Discussion Overview

The discussion revolves around the concept of generating static electricity using spinning disks made of dissimilar materials. Participants explore the feasibility of charge accumulation without direct contact between the disks, the effects of magnetic levitation, and the influence of permanent magnets on charge buildup. The scope includes theoretical considerations and practical applications related to electrostatic machines.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Jason O inquires whether static charge can build up on two spinning disks without them touching, suggesting a separation of about 1/16 inch.
  • Some participants reference the Wimshurst machine as a related concept, indicating that contact may not be necessary for charge generation.
  • Jason O poses additional questions about mechanical friction affecting the bottom disk's rotation due to charge attraction when the top disk is magnetically levitated.
  • There is uncertainty about whether the presence of permanent magnetic fields would influence charge buildup on the disks.
  • Jason O seeks clarification on whether his project aligns with the definition of an influence electrostatic machine, emphasizing the desire to avoid any physical contact between parts.
  • Jason O wonders if a static charge can be induced by a permanent magnet when a disk is spun near its pole.

Areas of Agreement / Disagreement

Participants do not reach a consensus on several points, including the effects of magnetic fields on charge buildup and the definition of an influence machine. Multiple competing views and uncertainties remain throughout the discussion.

Contextual Notes

Limitations include the lack of detailed exploration into the specific materials for the disks, the exact mechanics of charge interaction, and the potential effects of environmental factors on the experiment.

Jdo300
Messages
548
Reaction score
5
Hello, I am working on a project involving static electricity. I am trying to build a motor type device that can accumulate a static charge through two disks made of dissimilar materials (I’m still working out which two materials would be best) spinning past each other in close proximity. I’m wondering if it is possible for a static charge to build up on the two disks if they are spun close to one another (say with about 1/16 in separation between them. Or do the disks have to be touching/sliding on each other for this to work? I would like to use smooth materials for this experiment. Could someone please enlighten me on this?

Thanks,
Jason O
 
Engineering news on Phys.org
Thank you for the reference. What I am working on is vaguely similar to a Wimherst machine. My question is answered about weather the disks have to be in contact (they don't) to generate a charge, right?

Well, I have a few other questions as well. If I were to use two solid disks spinning close to each other, only facing horizontally one above the other on a vertical shaft, and I had the top disk magnetically levitated above the first, when the static charge builds up, would there be any kind of mechanical friction that would try to slow down the movement of the bottom disk? In this example, I plan to rotate only the bottom disk and fix the top one to the shaft (which is also non-moving). My idea is to eliminate as much friction between the two disks as possible. I know that the disks will want to attract each other when they become charged, but as far as rotational force goes, what they be slowed down from the static charge present? Also one more thing: would the presence of permanent magnet fields have any effect on the charge buildup on the disks?

Thank you,
Jason O
 
Thank you for the resource link. It looks like I need to do more reading up on the Wimherst and other electrostatic machines. I'm not sure but I think what I am trying to make is similar to an influence electrostatic machine. The whole idea is that I don't want any parts rubbing, rolling, or brushing up against each other to create the charge. Would that be the correct definition of an influence machine?

Well, I came up with yet another question, and this one I have had some trouble finding information on. Perhaps someone here could help me out :smile: I'm wondering if it is possible to induce a static charge using a permanent magnet. (Ex: spinning a disk next to the pole of a magnet). Would that cause charges to collect?
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
4K
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 20 ·
Replies
20
Views
2K
Replies
5
Views
3K
  • · Replies 4 ·
Replies
4
Views
3K
Replies
14
Views
2K
  • · Replies 9 ·
Replies
9
Views
5K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 7 ·
Replies
7
Views
4K