Wave Optics - Result Question 19

19. If yellow light emitted by sodium lamp in Young’s double slit experiment is replaced by a monochromatic blue light of the same intensity

(a) fringe width will decrease

[1992]

(b) finge width will increase

(c) fringe width will remain unchanged

(d) fringes will become less intense

Show Answer

Answer:

Correct Answer: 19. (a)

Solution:

  1. (a) As $\beta=\frac{\lambda D}{d}$ and $\lambda_b<\lambda_y$,

Fringe width $\beta$ will decrease