Why Do I Get Electrically Shocked by Metal Objects?

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Discussion Overview

The discussion centers around the phenomenon of experiencing electric shocks when touching metal objects, particularly in relation to temperature and humidity conditions. Participants explore potential explanations, including comparisons to the Seebeck effect and the role of static electricity.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that the shocks may be related to temperature differences between the person and the metal, questioning if it is similar to the Seebeck effect.
  • Another participant notes that shocks are more common in colder weather due to drier air, which affects the discharge of static electricity.
  • A third participant agrees with the Seebeck effect analogy, explaining that charge separation leads to electron flow when touching a metal object, but distinguishes between static and current electricity.
  • One participant challenges the analogy, arguing that equating thermal energy-induced charge motion with mechanical energy-induced charge separation is misleading, attributing winter shocks to conditions that allow charge buildup due to friction and induction.
  • A further elaboration on the Seebeck effect is provided, discussing thermodynamic factors and contrasting it with electrostatic discharge mechanisms, ultimately asserting that the two processes are not similar.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between the Seebeck effect and the phenomenon of electric shocks, with some agreeing on the influence of environmental conditions while others contest the comparisons made. The discussion remains unresolved with multiple competing explanations presented.

Contextual Notes

Participants reference various physical principles and effects, but the discussion includes unresolved assumptions regarding the mechanisms of charge separation and the conditions leading to electric shocks.

planck999
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Whenever I touch to a doorknob or any other metallic object I get electrically shocked. Does this occur because of temperature difference between me and the metal? Is it similar to seebeck effect?
 
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Does this happen to you mainly when it's cold outside?
The air is drier when the temperature is lower because in cold temperatures less moisture can be carried by the air. Which means static electricity cannot discharge that efficiently, hence more electrostatic shocks during winter (or autumn).
 
Yes it is similar to Seebeck. In each case conditions cause electrons to gather more on one side than the other and when there is a closed loop path, like you touching the doorknob, electrons will flow—the more electrons that flow the more shocking. Some people will say it’s “static electricity” but static electricity doesn’t actually do anything. It just sits there waiting. It is “current electricity” that is shocking. I am told there are numerous explanations of the foregoing from doing a Google search.
 
Hmm. I would say it’s stretching things a bit to equate motion of charges due to thermal energy and charge separation due to mechanical energy.
The sparks in winter are due to the drastic reduction in the saturation of cold air when it warms up indoors. Those (insulating) conditions allow charges to build up when separated by friction and induction.
 
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The Seebeck effect can be attributed to two things:
Thermodynamic-chemical potential { electric charge-carrier diffusion and phonon drag.}
- It conducts from DC to a relatively slow response change in thermal difference to each side of different materials.

Electrostatic discharge
Is only caused by triboelectric friction of moving electrons freely liberated to receptor insulators that arc rapidly when the breakdown voltage to differing charge potential exceeds threshold after an ionization time.

It will discharge in pico to microseconds depending on the gap length (door knob to low clouds) and inductance L and charge level whose density lowers the positive ESR resistance while the incremental resistance is negative.

Therefore I see no similarity in current transfer mechanisms.
 
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