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प्रश्न
Obtain the equation for critical angle.
उत्तर
The angle of incidence in the denser medium for which the refracted ray grace the boundary is called the critical angle.
Snell’s law in Product form
n1 sin ic = n2 sin 90°
n1 sin ic = n2
sin ic = `"n"_2/"n"_1`
here n1 > n2,
If the rarer medium is air
n1 = n and n2 = 1
sin ic = `1/"n"`
ic = sin-1 `1/"n"`
Critical angle and total internal reflection
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