Question

Light waves from two coherent sources arrive at two points on a screen with path difference of zero and \( \lambda / 2 \). The ratio of the intensities at the points is

• A. two : one
• B. one : two
• C. one : one
• D. infinity : one

Hint:

In interference, constructive interference results in maximum intensity and destructive interference results in minimum intensity (or zero in perfect destructive interference).

Answer 1

The Correct Option is D

Step 1: Understanding the interference pattern.
For two coherent sources, the interference pattern depends on the phase difference between the waves. If the path difference is zero, the waves will interfere constructively, resulting in maximum intensity. For a path difference of \( \lambda / 2 \), the interference will be destructive, resulting in zero intensity. Step 2: Conclusion.
Thus, the ratio of the intensities at the points is infinity to one, corresponding to option (D).