A light of ray is incident at an angle of 58degrees on the plane surface of a block of glass of refractive index 1.60. Some light is reflected on the other side of the normal at the same angle as the angle of incidence.
Find:
a.the angle between the light reflected from the surface and the light refracted into the glass
b.the deviation of the refracted ray
(a) sin r = sini/n =sin 58°/1.6=0.53
r =32 °
α=180°-58°-32°=90°
(b) δ= 58 -32 =26°
To find the required angles and deviation, we can use Snell's Law and the concept of total internal reflection. Snell's Law relates the angle of incidence and angle of refraction when light passes through the interface between two media.
a. Angle between the reflected light and the refracted light:
1. Determine the angle of refraction using Snell's Law: n1 * sin(angle of incidence) = n2 * sin(angle of refraction)
In this case, n1 is the refractive index of the initial medium (air) and n2 is the refractive index of the glass.
n1 = 1 (since the medium is air)
n2 = 1.60 (refractive index of glass)
2. Rearrange Snell's Law to solve for the angle of refraction:
sin(angle of refraction) = (n1 / n2) * sin(angle of incidence)
3. Substitute the given values and calculate the angle of refraction.
4. The angle between the reflected light and the refracted light will be the same as the angle of incidence.
Therefore, the angle between the light reflected from the surface and the light refracted into the glass is 58 degrees.
b. Deviation of the refracted ray:
1. Deviation is the change in direction of the refracted ray as it passes through the interface of the two media.
2. Calculate the angle of deviation using the formula: angle of deviation = angle of incidence - angle of refraction
3. Substitute the given values and calculate the angle of deviation.
Note: Total internal reflection occurs when the angle of incidence exceeds the critical angle, which is the angle at which the angle of refraction becomes 90 degrees.