Question

In a biprism expeirment , light of wavelenght 5200Å is ued to get an interference pattern on a screen. The fringe width changes by `0.13` mm when the screen is brought towards the biprism by 50 cm . The distance between the virtual images of the slit is
A. 0 mm
B. 1 mm
C. `0.5` mm
D. 2 cm

Answer 1

Correct Answer - A
`(beta_(2)-beta_(1))=((D_(2)-D_(1))lamda)/(d)`
`:.d=(0.5xx5.2xx10^(-7))/(1.3xx10^(-4))=2mm`