Page 1 - HA-refraction through prism

Objective Questions:

Q1: The critical angle between an equilateral prism and air is 45. If the incident ray is
perpendicular to the refracting surface, then

a. It is reflected totally from the second surface and emerges perpendicular from the
third surface.
b. It gets reflected from second and third surfaces and emerges from the first surface
c. It keeps reflecting from all the three sides of the prism and never emerges out
d. After deviation, it gets refracted from the second surface

Answer: (a) It is reflected totally from the second surface and emerges perpendicular
from the third surface.
Q2: Which ray is least deviated by a prism?

a. Violet ray
b. Green ray
c. Red ray
d. Yellow ray

Answer: (c) Red ray

Q3: A prism (μ=1.5) has a refracting angle of 30 . The deviation of a monochromatic ray
0
incident normally on its one surface will be

a. 18 36’
0
b. 20 30’
0
c. 18
0
d. 19 30’
0
Answer: (a) 18 36’
0
Q4: The angle of the prism is equal to the angle of minimum deviation for a prism of
refractive index 1.5. What is the value of the angle of the prism?

a. 41
0
b. 82
0
c. 62
0
d. 31
0
Answer: (b) 82
0
Q5: The dispersive power of prism depends upon

a. The shape of the prism
b. The material of the prism
c. The angle of the prism
d. Height of the prism

Answer: (b) The material of the prism