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Question
Draw the ray diagram of a glass slab having medium A and B for the velocity of light ray VA and VB respectively and define Snell's law.
- If VB = 1.5 VA, then which medium is denser?
- What is the refractive index of A with respect to B?
- What is the refractive index of B with respect to A?
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Solution
Where i = angle of incidence,
r = angle of refraction,
e = angle of emergence
At point N, using snell's law
AηB = `sin "i"/sin "r"` = constant
According to snell's law, the sin i of the angle of incidence to the sin r of the angle of refraction is always constant.
- Medium A is denser.
- Refractive index of A with respect to B is:
BηA = `"V"_"B"/"V"_"A" = (1.5 "V"_"A")/"V"_"A" = 3/2` - Refractive index of B with respect to A is:
AηB = `1/(""_"B"η_"A") = 2/3`
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