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# Confused about total internal reflection watch

1. Can you get a critical angle for air to water interface? Or can you get total internal reflection in air when the incident ray hits water boundary from air?

The equation: sinqc = n2 / n1 for n1> n2 (can't type theta symbol)
but... n1 = air = 1 n2 = water = 1.34
so... n1 < n2 which can’t be calculated?

Is the attached diagram possible?
Attached Images

2. (Original post by Da Bee)
Can you get a critical angle for air to water interface? Or can you get total internal reflection in air when the incident ray hits water boundary from air?

The equation: sinqc = n2 / n1 for n1> n2 (can't type theta symbol)
but... n1 = air = 1 n2 = water = 1.34
so... n1 < n2 which can’t be calculated?

Is the attached diagram possible?
For reflection the size of the incident angle is equal to the size of the angle of the reflected ray.

AFAIK the proportion of the incident light that gets reflected by the surface of a medium such as water is something that's always glossed over at A level - if you do any demos in the classroom you'll see that there's always some light that bounces off but you don't have to worry about why all the incoming photons don't do exactly the same thing at this level.
if you want more insight you could look at the book QED by Feynmann (though he talks about glass)
3. Okay thanks I'll just pray that I'll only encounter easy questions in the exam

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