MHTCET 15 Apr 2026 Shift 1 Paper

Concept:For a single slit diffraction pattern, the angular fringe separation depends only on the slit width and the wavelength of light, not on the screen distance.Explanation:The positions of the minima in single slit diffraction are given by:$$a \sin \theta = n \lambda$$Here, $a$ is the slit width, $\lambda$ is the wavelength, $\theta$ is the angular position, and $n$ is the order of the minimum.For small angles, $\sin \theta \approx \theta$, so we can write:$$\theta = \frac{n \lambda}{a}$$This expression shows that $\theta$ depends only on $\lambda$ and $a$.It does not contain the screen distance $D$.Therefore, when the slit-to-screen distance is doubled, the angular separation between fringes remains unchanged.Only the linear separation on the screen would change because it is given by $y = D\theta$.But the question asks about the angular separation, which is independent of $D$.Answer:The angular separation remains the same.Correct option: C. remains same.