Do diamonds reflect EM waves ?

Click For Summary

Discussion Overview

The discussion centers around the reflective properties of diamonds concerning electromagnetic (EM) waves, including visible light and sound waves. Participants explore various aspects of reflection, refraction, and the potential for charging diamonds with electromagnetism, touching on both theoretical and practical implications.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants assert that diamonds reflect EM waves, particularly in the visible spectrum (440nm to 770nm), under certain angles.
  • Others note that while diamonds can reflect some waves, they do not reflect all waves at all times, mentioning specific conditions like the Bragg angle for x-ray reflection.
  • It is proposed that any material with a refractive index different from one will reflect some EM radiation, with diamonds following Fresnel reflection principles.
  • Participants clarify that sound is not an EM wave, but diamonds can reflect sound effectively due to impedance mismatch when in air.
  • Questions arise about the possibility of "charging" diamonds with electromagnetism, with some participants seeking clarification on what "charging" entails.
  • There is a humorous suggestion that using amber or other materials might be more effective for generating static electricity than diamonds.

Areas of Agreement / Disagreement

Participants express a range of views on the reflective properties of diamonds, with no consensus reached on the specifics of charging diamonds or the effectiveness of diamonds compared to other materials for static electricity generation.

Contextual Notes

Some discussions involve assumptions about the definitions of "charging" and the conditions under which diamonds reflect various types of waves, which remain unresolved.

sbratva
Messages
5
Reaction score
0
Radio or any other wave in electromagnetic spectrum?

Sound perhaps?

And at what frequency(ies)
 
Physics news on Phys.org
Well, at an oblique enough angle, they'll certainly reflect EM waves between 440nm and 770nm. Of that we can be sure.
 
  • Like
Likes   Reactions: sbratva
sbratva said:
any other wave in electromagnetic spectrum?
Visible light is part of the EM spectrum, and a diamond's particular talent at refracting that is why they're sold as horrendously expensive jewelry. (Optical reflection is just a special form of refraction.)
And just about everything solid reflects sound, in one way or another.
 
  • Like
Likes   Reactions: sbratva
The can reflect some waves sometimes, but they can't reflect all the waves all the times.

At the Bragg angle they reflect x-rays.
 
  • Like
Likes   Reactions: sbratva
Pretty much anything with index of refraction not equal to 1 will reflect some EM radiation at its surface (assuming it is surrounded by air or vacuum) in accordance with Fresnel reflection http://en.wikipedia.org/wiki/Fresnel_equations

Metals are a weird case because they have complex refractive indices, but diamond simply follows the equation.
 
  • Like
Likes   Reactions: sbratva
Sound is not an EM wave but diamond will reflect it as well. Actually it will reflect is very well if the diamond is in air, as the impedance mismatch is huge.
 
  • Like
Likes   Reactions: sbratva
Thanks for replies fellas.

Last question.

Can you "charge" diamonds (rough) with let's say, electromagnetism?
 
sbratva said:
Can you "charge" diamonds (rough) with let's say, electromagnetism?
http://en.wikipedia.org/wiki/Material_properties_of_diamond

Except for most natural blue diamonds, which are semiconductors due to substitutional boron impurities replacing carbon atoms, diamond is a good electrical insulator, having a resistivity of 100 GΩ·m to 1 EΩ·m[28] (1011 to 1018 Ω·m).
There's a lot more to the article, but this is as far as I dare quote due to copyright.
 
sbratva said:
Thanks for replies fellas.

Last question.

Can you "charge" diamonds (rough) with let's say, electromagnetism?
What do you mean by "charge"? Charge with what?
 
  • #10
sbratva said:
Thanks for replies fellas.
Can you "charge" diamonds (rough) with let's say, electromagnetism?

Like, get a cat and rub the diamond on the cat and notice the static electricity?
"If you like it then you should have put a ring on it."
 
  • #11
  • #12
nasu said:
Sound is not an EM wave but diamond will reflect it as well. Actually it will reflect is very well if the diamond is in air, as the impedance mismatch is huge.
I would like to be able to afford a big enough diamond to have any significant reflections out in the open! :)
A lady / fiancee with particularly big hands needed too.
Diamond is like all solids, being much more dense than air - and a pretty stiff material, too.
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
1K
  • · Replies 21 ·
Replies
21
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 16 ·
Replies
16
Views
1K
  • · Replies 28 ·
Replies
28
Views
6K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 15 ·
Replies
15
Views
3K
  • · Replies 5 ·
Replies
5
Views
930
  • · Replies 10 ·
Replies
10
Views
2K