Necessary condition for obtaining an interference pattern when light waves (of same frequency) from two points S1 and S2 superpose is:
|
Intensity of two waves |
Phase difference between the two waves at S1 and S2 must be |
|
|
1) |
Must be equal |
Zero |
|
2) |
Must be equal |
π |
|
3) |
Must be equal |
Constant with time but not necessarily zero |
|
4) |
Need not be equal |
Constant with time but not necessarily zero |
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