Q. If $I_{0}$ is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled?
A) $2I_{0}$
B) $4I_{0}$
C) $I_{0}$
D) $\frac{I_{0}}{2}$
Explanation
(c) $I = I_{0}\left( \frac{\sin\theta}{\theta} \right)^{2}$
And $\theta = \frac{\pi}{\lambda}\left( \frac{ay}{D} \right)$
For principal maximum $y = 0$
$\therefore\ \theta = 0$
Hence, intensity will remain same.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.