Light interference question

  • #1
How come we dont see light interference from two light sources?

ex. two candles
 

Answers and Replies

  • #2
OlderDan
Science Advisor
Homework Helper
3,021
2
bullroar_86 said:
How come we dont see light interference from two light sources?

ex. two candles

There has to be a definite phase relationship between light from a source following different paths to produce an interference pattern. There is no definite phase relationship between light from two sources.
 
  • #3
870
0
Light emitted from regular light sources such as light globes, candles, etc... undergo very rapid phase changes, about 10 every billionth of a second. So although the light from two candles do actually interfere with each other (if they didnt then the emitted light would not obey the laws of physics now would they!?), the periods of destructive interference last for about 10 billionths of second. The result is that no interference effects are observed by the human eye and the light source is termed incoherent.

So we do not see light interference from two candles because our eyes are not sensitive enough to see it (and this is a result from the fact that there is not a definite phase relationship - as Older Dan has said).
 

Related Threads on Light interference question

  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
6
Views
8K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
1
Views
486
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
1
Views
7K
Replies
5
Views
997
  • Last Post
Replies
0
Views
1K
  • Last Post
Replies
0
Views
1K
  • Last Post
Replies
6
Views
2K
Top