For Young’s Double Slit Experiment, the fringe width \( \beta \) is given by:
\[
\beta = \frac{\lambda D}{d}
\]
where:
- \( \lambda \) = wavelength of light
- \( D \) = distance between slits and screen
- \( d \) = separation between slits
Since \( \beta \propto \lambda \), the fringe width increases with wavelength.