Attracting small splinters of glass with a Van de Graaff generator

Click For Summary
SUMMARY

The discussion centers on using a Van de Graaff generator (VDG) to attract tiny glass splinters in a container factory. The user connected a charged rod to the VDG sphere but observed inconsistent attraction of the splinters, which sometimes orient towards the rod but do not move. The primary issues identified are insufficient charge magnitude and charge transfer causing repulsion. Suggestions include using water to remove splinters and exploring shielding methods to prevent charge transfer while still attracting the splinters.

PREREQUISITES
  • Understanding of electrostatics and charge interactions
  • Familiarity with Van de Graaff generators
  • Knowledge of friction and its effects on charged particles
  • Basic principles of static electricity and charge transfer
NEXT STEPS
  • Research methods to increase charge magnitude on a Van de Graaff generator
  • Explore non-conductive shielding materials to prevent charge transfer
  • Investigate alternative methods for removing glass splinters, such as air jets
  • Learn about the principles of electrostatic attraction and repulsion
USEFUL FOR

Factory engineers, electrostatics enthusiasts, and anyone involved in manufacturing processes that require the removal of small debris or contaminants.

riseandsinh
Messages
2
Reaction score
0
Hello,

I work for a container factory where re-used bottles have a lot of tiny glass splinters. Inspired by the standard experiment of picking up glass splinters using a comb, I thought I could insert a charged rod into a bottle to attract little splinters towards it. To get similar voltages as a comb, I bought a small tabletop Van De Graaff generator.

I took a rod, connected it to the VDG sphere, and tried placing a few splinters close to it. The splinters don't seem to get attracted to the rod in any consistent way. Some of them 'orient' themselves towards the rod, but don't move towards it. Some touch the rod and then repel. I don't know how to proceed from now - could anyone please throw some light on this? My ultimate aim is to get rid of the splinters in whatever way possible.

I'm new here, so please let me know if I should re-post this in a more appropriate sub-forum. Thanks a lot in advance!
 
Physics news on Phys.org
riseandsinh said:
Hello,
I took a rod, connected it to the VDG sphere, and tried placing a few splinters close to it. The splinters don't seem to get attracted to the rod in any consistent way. Some of them 'orient' themselves towards the rod, but don't move towards it.

That's because the rod isn't charged enough for the splinters to overcome the friction of the surface they're sitting on and start moving towards the rod.

Some touch the rod and then repel.

That's because when the splinters hit the rod, the charge on the rod tries to spread out across the splinters. The splinters will then have the same charge as the rod and repel it.

I don't know how to proceed from now - could anyone please throw some light on this? My ultimate aim is to get rid of the splinters in whatever way possible.

What's wrong with filling them up with water, giving them a good shake, and dumping out the water? That seems fast and reliable.
 
Thank you for the quick reply, I was suspecting the low charge magnitude and the charge transfer were causing these problems.

ideasrule said:
That's because when the splinters hit the rod, the charge on the rod tries to spread out across the splinters. The splinters will then have the same charge as the rod and repel it.

Would it be possible to shield the sphere in some way so that the splinters do get attracted to it, but there is no charge transfer (and so no repelling, so they will stick to it)? I tried a plastic and paper coating, but that did not work.

ideasrule said:
What's wrong with filling them up with water, giving them a good shake, and dumping out the water? That seems fast and reliable.

That is a nice idea, and we have a similar system working with a jet of air. The problem is that this severely limits the rate of bottle production. We have rates in excess of 60 bottles a minute, so this causes problems.

Please let me know if there's anything else you have in mind, as I'm really stuck with this :(
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
5
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 8 ·
Replies
8
Views
7K
  • · Replies 7 ·
Replies
7
Views
4K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 20 ·
Replies
20
Views
5K