MEDIUM
12th West Bengal Board
IMPORTANT
Earn 100

A beam of light consisting of two wavelengths 600 nm and 500 nm is used to obtain fringes in a Young's double slit experiment. Separation between the slits is 2 mm and the screen is placed 120 cm away from the slits. Find the least distance from the central bright fringe where the bright fringe due to both the wavelength coincide. 

Important Questions on Wave Optics

EASY
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 5
Laser light of wavelength 640 nm incident on pair of slits produces an interference pattern in which the bright fringes are separated by 7.2 mm. Calculate the wavelength of another source of light which produces interference fringes separated by 8.1 mm using the same arrangement.
MEDIUM
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 6
A beam of light consisting of two wavelengths, 800 nm and 600 nm is used to obtain the interference fringes in Young's double slit experiment on a screen placed 1.4 m away. If the two slits are separated by 0.28 mm. Calculate the least distance from the central bright maximum where the bright fringe of the two wavelengths coincide.
MEDIUM
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 7
In Young's double slit experiment, the two slits 0.15mm apart are illuminated by monochromatic light of wavelength 450nm. The screen is 1.0m away from the slits. Find the distance of the second bright fringe,
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 7
In Young's double slit experiment, the two slits 0.15mm apart are illuminated by monochromatic light of wavelength 450nm. The screen is 1.0m away from the slits. Find the distance of the second (i) bright fringe, (ii) dark fringe from the maximum.
EASY
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 7
In Young's double-slit experiment, two slits are 0.15 mm apart and illuminated by light of wavelength 450 nm. The screen is 1 m away from the slits. How will the fringe pattern change, if the screen is moved away from the slits ?
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 8
In Young's double slit experiment, monochromatic light of wavelength 630 nm illuminates the pair of slits and produces an interference pattern in which two consecutive bright fringes are separated by 8.1 mm. Another source of monochromatic light produces the interference pattern in which the two consecutive bright fringes are separated by 7.2 mm. Find the wavelength of light from the second source. What is the effect on the interference fringes if the monochromatic source is replaced by a source of white light.
MEDIUM
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 9
In a two slits experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the slits. If the screen is moved by 5×10-2 m towards the slits, the change in the fringe width is 3×10-5 m. If the distance between the slits is 10-3 m, calculate the wavelength of light used 
HARD
12th West Bengal Board
IMPORTANT
A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 17 - Wave Optics>EXERCISE 17>Q 10
In Young's double slit experiment, using light of wavelength 400 nm, interference fringes of width x is obtained. The wavelength of light is increased to 600 nm and the separation between the slits is halved. If one wants the observed fringe width on the screen to be the same in the two cases, find the ratio of the distances between the screen and the plane of the interfering sources in the two arrangements.