0

Guest

Courses New

A thin paper of thickness 0.02 mm having a refractive index 1.45 is pasted across one of the slits in a Young’s double slit experiment. The paper transmits 4/9 of the light energy falling on it. (a) Find the ratio of the maximum intensity to the minimum intensity in the fringe pattern. (b) How many fringes will cross through the centre if an identical paper piece is pasted on the other slit also? The wavelength of the light used is 600 nm.

A thin paper of thickness 0.02 mm having a refractive index 1.45 is pasted across one of the slits in a Young’s double slit experiment. The paper transmits 4/9 of the light energy falling on it. (a) Find the ratio of the maximum intensity to the minimum intensity in the fringe pattern. (b) How many fringes will cross through the centre if an identical paper piece is pasted on the other slit also? The wavelength of the light used is 600 nm.

Grade:11

1 Answers

Aditi Chauhan
askIITians Faculty 396 Points
9 years ago
Sol. Given that, t = 0.02 mm = 0.02 * 10^–3m, μ base 1 = 1.45, λ = 600 nm = 600 * 10^–9 m a) Let, I base 1 = Intensity of source without paper = I b) Then I base 2 = Intensity of source with paper = (4/9)I ⇒ l base 1/l base 2 = 9/4 ⇒ r base 1/r base 2 = 3/2 [because l ∝ r^2] Where, r base 1 and r base 2 are corresponding amplitudes. So, l base max/l base min = (r base 1 + r base 2)^2/(r base 1 - r base 2)^2 = 25 : 1 b) No. of fringes that will cross the origin is given by, n = (μ – 1)/λ = (1.45 - 1) * 0.02 * 10^-3/600 * 10^-9 = 15.

Think You Can Provide A Better Answer ?

Other Related Questions on Wave Motion

View all Questions »

ASK QUESTION

Get your questions answered by the expert for free

Answer and earn gift vouchers

Win Gift vouchers upto Rs 500/-

View courses by askIITians

Design classes One-on-One in your own way with Top IITians/Medical Professionals

Click Here Know More

Complete Self Study Package designed by Industry Leading Experts

Click Here Know More

Live 1-1 coding classes to unleash the Creator in your Child

Click Here Know More

a Complete All-in-One Study package Fully Loaded inside a Tablet!

Click Here Know More