B M Sharma Solutions for Chapter: Wave Optics, Exercise 4: DPP

The Young's experiment is performed with the lights of blue $\left(\lambda =4366 \stackrel{\mathrm{o}}{\mathrm{A}}\right)$ and green colour $(\lambda =5460 \stackrel{\mathrm{o}}{\mathrm{A}})$. If the distance of the $4^{th}$ fringe from the centre is $x$, then

Two ideal slits $S_1$ and $S_2$ are at a distance $d$ apart and illuminated by light of wavelength $\lambda$, passing through an ideal source slit $S$, placed on the line through $S_2$, as shown. The distance between the planes of slits and the source slit is $D$. A screen is held at a distance $D$ from the plane of the slits. The minimum value of $d$ for which there is darkness at $O$ is

A beam with wavelength $\lambda$ falls on a stack of partially reflecting planes with separation $d$. The angle $\text{θ}$ that the beam should make with the planes so that the beams reflected from successive planes may interfere constructively is (where, $n=1, 2, ...$)

White light may be considered to be a mixture of waves with $\text{λ}$ ranging between $3900 \stackrel{\circ }{\mathrm{A}}$ and $7800 \stackrel{\circ }{\mathrm{A}}$. An oil film of thickness $10,000 \stackrel{\circ }{\mathrm{A}}$ is examined normally by reflected light. If $\text{μ}=1.4$, then the film appears bright for

A light of wavelength $5890 \stackrel{\circ }{\mathrm{A}}$ falls normally on a thin air film. The minimum thickness of the film such that the film appears dark in reflected light is

What is the effect on Fresnel's biprism experiment when the use of white light is made?

In a biprism experiment, by using light of wavelength $5000 \stackrel{\circ }{\mathrm{A}}, 5 \mathrm{mm}$ wide fringes are obtained on a screen $1.0 \mathrm{m}$ away from the coherent sources. The separation between the two coherent sources is

In Fresnel's biprism $(\mu =1.5)$ experiment, the distance between source and biprism is $0.3 \mathrm{m}$ and that between biprism and screen is $0.7 \mathrm{m}$ and angle of prism is $1°$. The fringe width with light of wavelength $6000 \stackrel{\circ }{\mathrm{A}}$ will be