Question

In YDSE, the intensity of the maxima is I. If the width of each slit is doubled the intensity of the maxima will be :

• A. I/2
• B. I
• C. 4I
• D. 2 I

Answer 1

The correct option is D 2 I

If maximum Intensity is $I$ then the incident intensity is $I/4$. When the slit width is doubled the area gets doubled thus Intensity is doubled. Thus incident intensity becomes $I/2$. If the incident intensity $I/2$ then the maxima intensity is four times the incident. Thus $2I$ is the maxima intensity.