Student Login

Home›Chapters›Wave Optics PYQs›YDSE: Fringe Width & Fringe Positions›Question 10

MHT CET 2026 (15 May, Shift 1) · YDSE: Fringe Width & Fringe Positions

YDSE: Fringe Width & Fringe Positions question from MHT CET 2026 (15 May, Shift 1)

Q10MHT CET 2026 · 15 MAY · SHIFT 1Medium

YDSE: Fringe Width & Fringe Positions

In double slit experiment, the angular width of the fringes is $0.20^\circ$ for sodium light ( $\lambda = 5890$ \AA). To increase the angular width of the fringes by $10\%$ , the necessary change in wavelength is

Show answer and solution

Answer: (d)

Angular width $\theta = \frac{\lambda}{d}$ , so $\theta \propto \lambda$ for fixed $d$ .
10% increase in $\theta$ needs 10% increase in $\lambda$ : $\Delta\lambda = 0.1\times5890 = 589$ Å
So the answer is (d) increase by 589 Å.

Report a mistake

More questions on YDSE: Fringe Width & Fringe Positions

In Young's double slit experiment the wavelength of light used is 6000 Å, the screen is…MHT CET 2025 (23 Apr, Shift 1)
In a Young's double slit experiment, the slits are separated by 0.2 mm. If the slits…JEE Main 2025 (4 Apr, Shift 1)
Given below are two statements. One is labelled as Assertion (A) and the other is…JEE Main 2025 (22 Jan, Shift 2)
In Young's double slit experiment, when light of wavelength 600 nm is used, 18 fringes…MHT CET 2025 (20 Apr, Shift 1)
Graph shows the variation of fringe width ( X) versus distance of the screen from the…MHT CET 2025 (26 Apr, Shift 2)
In Young's double slit experiment with monochromatic light of wavelength 600 nm, the…MHT CET 2025 (20 Apr, Shift 2)
The ratio of the distance of n th bright band and m th dark band from the central bright…MHT CET 2025 (26 Apr, Shift 1)
In a Young's double slit experiment wavelength of light used is 6000 Å. The first order…MHT CET 2025 (22 Apr, Shift 1)