Optics Question 1117
Question: In a double slit experiment, instead of taking slits of equal widths, one slit is made twice as wide as the other. Then in the interference pattern
[IIT-JEE (Screening) 2000]
Options:
A) The intensities of both the maxima and the minima increase
B) The intensity of maxima increases and the minima has zero intensity
C) The intensity of maxima decreases and that of the minima increases
D) The intensity of maxima decreases and the minima has zero intensity
Show Answer
Answer:
Correct Answer: A
Solution:
In interference between waves of equal amplitudes a, the minimum intensity is zero and the maximum intensity is proportional to 4a2.
For waves of unequal amplitudes a and A(A >a), the minimum intensity is non zero and the maximum intensity is proportional to (a + A)2, which is greater than 4a2.