Q 12-10-003NEETNEET 2024Top questionEasy
If the monochromatic source in Young's double slit experiment is replaced by white light, then
Answer: (A) there will be a central bright white fringe surrounded by a few coloured fringes.
Concept. At the centre the path difference is zero for every wavelength; elsewhere fringe positions depend on $\lambda$.
Step 1. Centre. All colours are bright there: a white central fringe.
Step 2. Away from the centre. $\beta = \dfrac{\lambda D}{d}$ differs for each colour, giving a few coloured fringes before the pattern washes out.
Answer. There will be a central bright white fringe surrounded by a few coloured fringes (Option A).
Solution by Sreeraj P, M.Sc Physics