1. Tardigrade
  2. Question
  3. Physics
  4. In a certain double slit experimental arrangement, interference fringes of width 1 mm each are observed when light of wavelength 5000 mathringA is used. Keeping the setup unaltered, if the source is replaced by another of wavelength 6000 mathringA, the fringe width will be

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. In a certain double slit experimental arrangement, interference fringes of width 1 mm each are observed when light of wavelength $5000 \mathring{A}$ is used. Keeping the setup unaltered, if the source is replaced by another of wavelength $6000 \mathring{A}$, the fringe width will be

KEAMKEAM 2007Wave Optics

Solution:

Fringe width, $\beta=\frac{\lambda D}{d}$
Since D and d are unaltered, $\beta \infty \lambda$
$\therefore \frac{\beta'}{\beta} \frac{\lambda'}{\lambda}$
or $\beta'=\beta\times\frac{\lambda'}{\lambda}=1\times\frac{6000}{5000}=1.2$ mm