How to Apply Snell's Law Without Knowing the Index of Refraction?

[Hello2016]

Homework Statement

[/B]
I know that the depth is 30 cm , the apprared depth to the observer is 15 cm. But how am i going to use snells law to get the refracted and incident angle when i have no idea what the index of refraction is for n2 liquid? ?

Homework Equations

N1sin1=n2sin2

The Attempt at a Solution

Im trying to use smells law to figure out both angles but I am missing the index of refraction and i don't know how to compute it using the depth and length givenhttps://www.physicsforums.com/attachments/93432

 

[nrqed]

Homework Statement

I know that the depth is 30 cm , the apprared depth to the observer is 15 cm. But how am i going to use snells law to get the refracted and incident angle when i have no idea what the index of refraction is for n2 liquid? ?[/B]

Homework Equations

N1sin1=n2sin2

The Attempt at a Solution

Im trying to use smells law to figure out both angles but I am missing the index of refraction and i don't know how to compute it using the depth and length givenhttps://www.physicsforums.com/attachments/93432

You need to figure out the angles using geometry, from the figure drawn. Only after that do you use Snell's law to find the index of refraction.

 

[Hello2016]

You need to figure out the angles using geometry, from the figure drawn. Only after that do you use Snell's law to find the index of refraction.

Oh so like tan sin and cos?

 

[nrqed]

Oh so like tan sin and cos?

Yes, draw right angle triangles, use the apparent and real depths to get the sides of some triangles and then use trigonometry to find the angles.

 

[Hello2016]

Hey I am not sure how i should use x in the geometry