MHT CET202618 April 2026Morning ShiftPhysicsWave OpticsActual
In a certain region of the screen, number of fringes formed is observed to be 8 in Young's double slit experiment when light of wavelength 6600 Å is used. If the light of wavelength 4400 Å is used, the number of fringes observed in the same region of the screen will be
Options
- A10
- B12
- C16
- D18
Correct answer
B. 12
Step-by-step solution
Let the width of the region on the screen be y . The fringe width is given by = D d The number of fringes n in the region y is n = y = y d D For a fixed region, n 1 n₁ ₁ = n₂ ₂ Given n₁ = 8 , ₁ = 6600 Å , and ₂ = 4400 Å 8 6600 = n₂ 4400 n₂ = 8 6600 4400 = 12 Answer: 12