White light is used to illuminate the two slits in Young’s double-slit experiment. The separation between the slits is $b$, and the screen is at a distance $D$ ($>b$) from the slits. At a point on the screen directly in front of one of the slits, certain wavelengths are missing. Some of these missing wavelengths are

While conducting the Young's double-slit experiment, a student replaced two slits with a large opaque plate in the $x-y$ plane containing two small holes that act as two coherent point sources $(S_1, S_2)$ emitting light of wavelength $600 \mathrm{nm}.$ The student mistakenly placed the screen parallel to the $x-z$ plane $(z> 0)$ at a distance$D= 3 \mathrm{m}$ from the mid-point of$S_1{S}_2,$as shown schematically in the figure. The distance between the sources $d=0.6003 \mathrm{mm}$. The origin $O$ is at the intersection of the screen and the line joining $S_1{S}_2.$ Which of the following is(are) true of the intensity pattern on the screen?

Two coherent monochromatic point sources $S_1$ and $S_2$ of wavelength $\mathrm{\lambda }= 600 \mathrm{nm}$are placed symmetrically on either side of the center of the circle as shown. The sources are separated by a distance $d= 1.8 \mathrm{mm}.$ This arrangement produces interference fringes visible as alternate bright and dark spots on the circumference of the circle. The angular separation between two consecutive bright spots is $∆\mathrm{\theta }.$ Which of the following options is/are correct?