Two very narrow slits are illuminated by monochromatic coherent light in air tha
ID: 1603287 • Letter: T
Question
Two very narrow slits are illuminated by monochromatic coherent light in air that has wavelength 560 nm and the interference pattern is observed on a screen that is 4.00 m from the slits. The first interference minima are located at plusminus 58.0 degree on either side of the central bright band. You then immerse the slits and the space between the slits and the screen in a transparent liquid and illuminate the slits with the same light. Now the first minima on either side of the central bright band occur at plusminus 36.0 degree. a) What is the distance between the two slits? b) What is the refractive index of the liquid?Explanation / Answer
In interference pattern
path difference = d*sintheta
for minima
path difference = m*lambda/2
d*sin(theta) = m*lambda/2
d*sin58 = 1*560*10^-9/2
d = 3.3*10^-7 m
==========================
(b)
In air
d*sintheta1 = m*lambda ..(1)
In liquid
wavelength = lambda/n
d*sintheta2 = m*lambda/n ..........(2)
n = refrative index
from 1 & 2
sintheta1/sintheta = n
n = sin58/sin36 = 1.44 <<<-----answer
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.