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.

Options

A. The intensities of both the maxima and the minima increase
B. The intensity of maxima increase 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

Answer

A

Explanation

If the amplitudes of the two waves are equal i.e., A and A. then the maximum intensity is proportional to `(A+A)^(2)` or `4A^(2)` and the minimum intensity is zero.
But if the amplitudes are A and 2A, then the minimum intensity cannot be zero, it is increased.
The maximum intensity will be proportional to `(A+2A)^(2)` or `9A^(2)`. this is more than `4A^(2)`. thus the intensities of both the maxima and the minima are increased.