(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 1.0-cm-thick layer of water stands on a horizontal slab of glass. Light from a source within the glass is incident on the glass-water boundary.

What is the maximum angle of incidence for which the light ray can emerge into the air above the water?

2. Relevant equations

Snell's Law: n_{i}sin[tex]\theta[/tex]_{i}= n_{t}sin[tex]\theta[/tex]_{t}

3. The attempt at a solution

I drew a diagram like this:

air (n = 1.00)

________________ light ray[tex]\uparrow[/tex]

water (n = 1.33) light ray[tex]\uparrow[/tex]

________________ light ray[tex]\uparrow[/tex]

glass (n = 1.50) light ray[tex]\uparrow[/tex]

The ray of light travels from the glass upward.

n_{glass}sin90 = n_{water}sin[tex]\theta[/tex]_{water}

n_{water}sin[tex]\theta[/tex]_{water}= n_{air}sin[tex]\theta[/tex]_{air}

Therefore, using equality of alternate angles:

n_{glass}sin90 = n_{air}sin[tex]\theta[/tex]_{air}

(1.50)*(sin90) = (1.00)*(sin[tex]\theta[/tex]_{air})

Solution: undefined

What is the maximum angle of incidence if it is undefined?

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# Homework Help: Undefined Angle of Incidence?

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