Question

A horizontal parallel-sided plate of glass having a refractive index of 1.56 is in contact with the surface tnk. A ray coming from above in air makes an angle of incidence of 32.5. with the normal to the top surface of the glass. Take refractive index of air 1 a) What is the angle of refraction on glass surface? (5 pts) of wa er i b) What is the critical angle of gla ss-water surface as explained above?

Answer 1

(I). The angle of refraction on glass surface is 20.12°

(II). The critical angle of glass-water surface is 61.0°.

Step-by-step explanation:

Given that,

Refractive index of glass = 1.56

Angle = 32.5

(I). We need to calculate the angle of refraction on glass surface

Using Snell's law

`n_(a)\sin i=n_(g)\sin r`

Put the value into the formula

`1*\sin32.5=1.56\sin\theta`

`\sin r=(1*\sin32.5)/(1.56)`

`r=\sin^(-1)0.344`

`r=20.12`

(II). We need to calculate the critical angle of glass-water surface

Using formula of critical angle

`\sin\theta_(c)=(n_(w))/(n_(a))`

`\theta_(c)=\sin^(-1)(1.33)/(1.52)`

`\theta_(c)=61.0^(\circ)`

Hence, (I). The angle of refraction on glass surface is 20.12°

(II). The critical angle of glass-water surface is 61.0°.