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Hi.
00:02
Here in this given problem, first of all there is a boundary separating medium number 1 from medium number 2.
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Then one more boundary separating again this medium number 2 from medium number 1 again.
00:25
It is repeated.
00:26
Array of light is entering while traveling in medium number 1 enters into this medium number 2 making an angle of incidence here, theta i.
00:46
Then it makes an angle of transmission here in this medium number 2, that is theta t.
00:57
The same angle will be serving as angle of incidence for the refraction of this ray of light again from medium number 2 to the medium number 1.
01:12
So angle of refraction here, sorry, angle of incidence here, that is also theta t.
01:22
And finally the ray of light will come back into the same medium, making this angle of refraction theta f we can say it to be.
01:38
Now, n1 means the index of refraction of medium 1.
01:44
This is given as 1 .05, n2, index of refraction of medium 2.
01:52
This is 1 .40.
01:55
Angle of incidence in the first medium, this is given as 60 .0 degree.
02:00
In the first part of the problem, we have to find angle of transmission, theta t.
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So using snell's law for the refraction from medium 1 to medium 2 it is given as index of refraction of the second medium with respect to the first one that is equal to sine theta i divided by sine theta t plugging in all the known values this is 1 .40 divided by 1 .05 is equal to sine 60 .0 degree and divided by sine theta t.
02:46
So we get an expression for this sine theta t and this is equal to sine 60 degree multiplied by 1 .05 divided by 1 .40 which comes out to be equal to 0 .6 so, finally, theta t here will be given by sine inverse of 0 .6495 means theta t is 40 .5 degree answer for the first part of the problem here...