Coherent and Incoherent Addition of Waves

In Young’s double slit experiment, the two slits 0.15 mm apart are illuminated by monochromic light of wavelength 450 nm. The screen is 1.0 m away from the slits.

(a) Find the distance of the second (i) bright fringe, (ii) dark fringe from the central maximum.

Which of the following expressions is/are correct for Young’s experiment?

(i) condition for bright fringes  $x=n\lambda \frac{D}{d}$

(ii) condition for dark fringes  $x=\left(2n-1\right)\frac{\lambda }{2}\frac{D}{d}$

ii) fringe width  $\beta =\frac{\lambda D}{d}$

A point source emits sound equally in all directions in a non-absorbing medium. Two points P and Q are at a distance of 9 metres and 25 metres respectively from the source. The ratio of amplitudes of the waves at P and Q is ___________

A point source emits sound equally in all directions in a non-absorbing medium. Two points P and Q are at a distance of 9 metres and 25 metres respectively from the source. The ratio of amplitudes of the waves at P and Q is ___________

Two beams of light having intensities I and 4I interfere to produce a fringe pattern on a screen. The phase difference between the beams is  $\frac{\pi }{2}$  at point A and  $\pi$ at point B. Then the difference between the resultant intensities at A and B is

A thin slice is cut out of a glass cylinder along a plane parallel to its axis. The slice is placed on a flat glass plate as shown in figure. The observed interference fringes from this combination shall be

Two coherent monochromatic light beams of intensities $\mathrm{I}$ and $\mathrm{4I}$ are superposed. The maximum and minimum possible intensities in the resulting beam are

Two coherent monochromatic light beams of intensities $I$ and $4I$ are superposed. The maximum and minimum possible intensities in the resulting beam are

Which is following statement is correct?

Ratio of intensities of two waves are given by $4:1$. Then the ratio of the amplitudes of the two waves is

One of the Young's double slits is covered with a glass plate as shown in the figure. The position of central maxima will:

Two coherent monochromatic light beams of intensities $I$ and $4I$ are superposed. The maximum and minimum possible intensities in the resulting beam are:

What is phase of a wave 

If the intensity ratio of two coherent sources used in Young's double slit experiment is $49:1$, then the ratio between the maximum and minimum intensities in the interference pattern is

A point is situated at $6.5\mathrm{cm}$ and $6.65\mathrm{cm}$ from two coherent sources. Find the nature of illumination at the point if wavelength of light is $5000\stackrel{\circ }{\mathrm{A}}$

Using analytical method, obtain an expression for the path difference between two light waves.

Find the ratio of intensities at two points x and y on a screen in Young's double-slit experiment, where waves from $S_1$ and $S_2$ have path
difference of (i) $0$ and (ii) $\frac{\lambda }{4}$

State the conditions to get constructive and destructive interference of light.

What are coherent sources? How are they produced?

Three waves arrive at a given point with a successive phase difference of $\frac{\pi }{2}$. The waves are of equal frequency and have amplitudes of $10 \mathrm{\mu m}$, $4 \mathrm{\mu m}$ and $7 \mathrm{\mu m}$. Find the amplitude of the resulting wave in $\mathrm{\mu m}$.