# Electrostatic Induction in Metals vs Insulators

• rdjohns12
In summary, when considering a small dielectric sphere and a point charge, as well as a small metallic sphere and a point charge, both will experience an attractive force due to electrostatic induction. However, the attractive force in the metallic case is typically greater than or equal to the attractive force in the dielectric case. This is due to the perfect screening in a conductor, which allows for a larger induced charge distribution to cancel out the field from the charge. This hypothesis can be confirmed by investigating the electric field at the point of the charge in both cases.
rdjohns12
If we have a small dielectric sphere and a point charge, they will experience an attractive force due to electrostatic induction. (From the elongation/rotation of charges bound to individual atoms).

Likewise, if we have a small metallic sphere and a point charge, they will experience an attractive force due to electrostatic induction. (From the displacement of the electron gas).

Can I accurately say that the attractive force for the metallic case is always greater than or essentially equal to the attractive force in the dielectric case?

I think this because the screening in conductor is perfect (i.e. infinite kappa), so the induced charge distribution will be large enough to cancel the entire field from the charge, whereas in the dielectric, the screening can be much worse or (for high kappa materials) at best approximately as good.

I have never seen this written down in quite the way I am asking it, so I am not sure if I am wrong.

vanhees71
You can investigate the electric field generated at the point of the charge for both the cases to confirm your hypothesis.

## 1. What is electrostatic induction?

Electrostatic induction is the process by which a charged object can influence the distribution of charges in a nearby neutral object, causing it to become polarized and develop a temporary charge imbalance.

## 2. How does electrostatic induction differ in metals and insulators?

In metals, charges are free to move and redistribute themselves, resulting in a quick and efficient induction process. In insulators, charges are not free to move and therefore the induction process is slower and less effective.

## 3. Can electrostatic induction occur between two insulators?

Yes, electrostatic induction can occur between two insulators, but the process will be slower and less effective compared to induction between a metal and an insulator.

## 4. What is the practical application of electrostatic induction in metals and insulators?

Electrostatic induction is used in various technologies, such as capacitors, electrostatic precipitators, and Van de Graaff generators. In metals, it is also used in grounding to prevent electrical shocks.

## 5. How does the distance between two objects affect electrostatic induction?

The closer the two objects are, the stronger the electrostatic induction will be. As the distance between the objects increases, the induction will become weaker and eventually no longer occur. This is because the influence of the charged object decreases with distance.

• Electromagnetism
Replies
3
Views
999
• Electromagnetism
Replies
4
Views
865
• Electromagnetism
Replies
1
Views
698
• Introductory Physics Homework Help
Replies
21
Views
665
• Electromagnetism
Replies
4
Views
2K
• Electromagnetism
Replies
4
Views
2K
• Electromagnetism
Replies
5
Views
1K
• Classical Physics
Replies
16
Views
362
• Electromagnetism
Replies
7
Views
2K
• Electromagnetism
Replies
8
Views
1K