How to Calculate θ3 After Finding θ2 Using Snell's Law?

[betterscientist]

Homework Statement

Block A has a refractive index of 1.52, Block B has a refractive index of 1.2, and Block C has a refractive index of 1.4.
A ray of light travels through air into Block A. Assume air has a refractive index of 1 and θ1 = 78°.
Calculate angles θ2-θ8.

Relevant Equations

n1sin(θ1)=n1sin(θ2)

I used Snell's law to find θ2 as 40,1 (3sf) but now I'm stuck on finding θ3.

Is there a way to find θ3 without using geometry? How do I do this?

 

[BvU]

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I'm stuck on finding θ3

How about using the same law again ?

Can you make (and post) a sketch of the situation ?

$\$

 

[betterscientist]

Apologies. I saw I have left out the image.

 

[BvU]

Good thing you now posted the picture. Differs from what I had in mind. And where is block C ? ?

 

[betterscientist]

Good thing you now posted the picture. Differs from what I had in mind. And where is block C ? ?

 

[betterscientist]

Sorry again. Cropped it out since it was irrelevant to the question I had issues with. I should have double checked my initial question/statement.

 

[BvU]

So far you found angle $X_1$. So $X_2 =$ ?
Now draw $\theta_3$ in the picture
Change of notation.
So far you found angle $\theta_2$. So $\theta_3 =$ ?

For $\theta_4$ you can use Snellius again. Etc..

$\$

 

[betterscientist]

So far you found angle $X_1$. So $X_2 =$ ?
Now draw $\theta_3$ in the picture
Change of notation.
So far you found angle $\theta_2$. So $\theta_3 =$ ?

For $\theta_4$ you can use Snellius again. Etc..

$\$

would theta 3 be the same as theta 2 (40,1)?

 

[haruspex]

would theta 3 be the same as theta 2 (40,1)?

Do they look the same?

 

[BvU]

Of course not.