- #1
jegues
- 1,097
- 3
Homework Statement
See figure attached.
Homework Equations
The Attempt at a Solution
Initially,
[tex]\theta_{c} = 60^{o}[/tex]
[tex]n_{glass}sin\theta_{c} = n_{air}[/tex]
So,
[tex]n_{glass} = \frac{n_{air}}{sin\theta_{c}}[/tex]
Now I would think that the incident angle from glass to air would be able to get LARGER and still remain critical because it would be less "head on" to the incident surface and thus less likely to refract through.
So if we assume, [tex]\theta_{c}[/tex] can get larger and still remain critical then if we take and angle say,
[tex]\theta_{c} = 85^{o}[/tex]
certainly,
[tex]n_{glass} = \frac{n_{air}}{sin\theta_{c}} < 1.15[/tex]
because the value of the denominator is getting larger.
However they give c) as the correct answer. What am I misunderstanding?