Homework Help

monochromatic light passes in three layers. Each medium are n1=2, n2=1,5, n3=1,2. Let...

user profile pic

handsofgod | (Level 2) eNoter

Posted July 2, 2013 at 8:12 AM via web

dislike 0 like

monochromatic light passes in three layers. Each medium are n1=2, n2=1,5, n3=1,2. Let the frequency and the speed of light in the vacuum be 5x10^14 Hz and 3x10^8 m/s.


1. calculate the speed of light in the second layer

2. calculate the wavelenght of light in the second layer

3. if the angle of incidence `theta` at the boundary B is larger than the critical angle `theta`c the total reflection occurs. Find the value if sin `theta`c

 

 

Images:
This image has been Flagged as inappropriate Click to unflag
Image (1 of 1)

1 Answer | Add Yours

user profile pic

llltkl | College Teacher | (Level 3) Valedictorian

Posted July 2, 2013 at 10:06 AM (Answer #1)

dislike 1 like

The question has too many parts, only parts 1 and b) are related. Hence these two are answered.

We know, `v_0=nulambda_0`

In vacuum, `3*10^8=5*10^14*lambda_0`

`rArr lambda_0=6*10^-7` m

Again, refractive index, `n_1` , in a medium with respect to vacuum can be expressed as

`n_1 = v_0/v_1=lambda_0/lambda_1`

and similarly,

 `n_2 = v_0/v_2=lambda_0/lambda_2`

a) Here, the second layer has a refractive index of 1.5

Therefore, `v_2=3*10^8/1.5 =2*10^8` m/s

b) Similarly, `lambda_2=6*10^-7/1.5=4*10^-7` m

Sources:

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes