# Refraction - A light ray is incedent on a block of glass at an angle of 30 degrees

1. May 10, 2012

### o0sunny0o

Refraction -- A light ray is incedent on a block of glass at an angle of 30 degrees

1. The problem statement, all variables and given/known data
A light ray is incedent on a block of glass at an angle of 30 degrees,what is the angle of refraction.

Given: glass: 1.47
incident angle:30°

2. Relevant equations

π1 sin θ1 = π2 sin θ2

3. The attempt at a solution

I did: (1.47) sin (30)= π2 sin θ2
But I don't think this is the answer. i'm helping a friend but the problem don't say what the other medium is...

Last edited: May 10, 2012
2. May 11, 2012

### collinsmark

Re: Refraction

Hello o0sunny0o,

Welcome to Physics Forums!
I'm guessing that the original medium is air. The second medium is glass.

I'll also assume that the 30o angle is measured with respect to the perpendicular*, and measured outside the glass (i.e. in the air). If so, treat your
n1 sinθ1 = n2 sinθ2
formula as
(Index of refraction of air)(sine of angle in air) = (index of refraction of glass)(sine of angle in glass)​

*The problem statement is is vague about what the angle is in reference to; perpendicular or parallel. I'm assuming it's in reference to the perpendicular, but that's just my assumption. I don't know for sure. A figure would certainly clear things up.

3. May 12, 2012

### o0sunny0o

Re: Refraction -- A light ray is incedent on a block of glass at an angle of 30 degre

thank you for the answer^^

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