In a Young's double slit experiment, (slit distanced) monochromatic light of wavelength λ is used and the figure pattern observed at a distance L from the slits. The angular position of the bright fringes is?

The correct option is A sin⁻¹(Nλd)
The path difference of light coming from two slits at height y from the central maxima = yd/L
Hence for the bright fringe to form, yd/L = Nλ
Hence y/L = Nλd
The angular position of bright fringe is θ = sin⁻¹(y/L) = sin⁻¹(Nλd)