Question

Light is incident at an angle Ï• with the normal to a plane containing two slits of separation d. Select the expression that correctly describes the positions of the interference maxima in terms of the incoming angle Ï• and outgoing angle θ.

                                                                     

Solution

Correct option is

 

Path difference = d sin Ï• + d sin θ 

For maxima,      

SIMILAR QUESTIONS

Q1

Two waves of same frequency have amplitude in the ratio 2:1. Find the ratio of the maximum and the minimum amplitudes and intensities in the region of interference. 

Q2

 

Two coherent sources X and Y of light of wavelength

λ = 6.2 × 10 –5 cm, produce interference. If both the sources are in the same phase and P is an arbitrary observation point, then calculate XP – YPwhen the point P is (i) At the bright band of 10th order, (ii) At the dark band between third and fourth order maxima.

Q3

In Young’s experiment on interference of light a fringe of width 0.04 cm is obtained on a screen placed at a distance of 50 cm from the slits when the wavelength of the light used is 5000 Ã…. If the distance of the screen from the slits remains unchanged, what will be the width of the fringe if light of wavelength 4000 Ã… is used? 

Q4

The fringe-width is obtained as 0.060 cm on using light of wavelength 5000Ã… in Young’s experiment. What value of wavelength of light should be taken so that the width of the fringe on the screen could be obtained as 0.040 m, if the distance of screen from the slit is halved?

Q5

 

In a two-slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the slits. If the screen is moved by  towards the slits, the change in fringe-width is . If the distance between the slits is 10–3 

M, calculate the wavelength of the light used. 

Q6

In Young’s experiment the interval between the slits is 0.200 mm. For the light of wavelength 600 mμ, interference fringes are formed on a screen at a distance of 80.0 cm. (i) What is the distance of the second dark fringe from the central fringe? (ii) What is the distance of the second bright fringe from the central fringe?   

Q7

Microwave from a transmitter are directed normally towards a plane reflector. A detector. A detector moves along the normal to the reflector. Between positions of 14 successive maxima the detector travels a distance 0.14 m. The frequency of the transmitter is (c = 3 × 108 m/s)    

Q8

In a Young’s double-slit experiment, the separation between the slits is d, distance between the slit and screen is D(D >> d). In the interference pattern, there is a maxima exactly in front of each slit. Then, the possible wavelength(s) used in the experiment are  

Q9

In a double-slit experiment, two parallel slits are illuminated first by light of wavelength 400 nm and then by light of unknown wavelength. The fourth-order dark fringe resulting from the known wavelength of light falls in the same place on the screen as the second-order bright fringe from the unknown wavelength. The value of unknown wavelength of the light is 

Q10

In Young’s double-slit experiment, the slits are illuminated by monochromatic light. The entire set-up is immersed in pure water. Which of the following act cannot restore the original fringe width?