Question

if the angle of incidence of a ray of light falling on the glass surface is 30 degree amd the angle of refraction is 19degree what is the refractive index of glass

Answer 1

Angle of Incidence = 30°
Angle of Refraction = 19°

refractive index of air is = 1
now using snell's law
u1 sin i = u2 sin r
where u1 is refractive index of air
u2 is refractive index of glass
i = angle of incidence
r = angle of refraction
1× sin30 = u2 × sin 19
1/2 = u2 × 0.325
u2 = 1.565..
so option 4 is correct

Answer 2

Given that

Angle of incidence = 30°

Angle of refrection = 19°

We know that Snell's laws

Angle of incidence : u + sini
Angle of refrection : u + sinr

u1 + 30 = u2 + 19°

u1 + 1/2 = u2 + 0.325

1/2 × 0.325 = u2

u2 = 1.565