CBSE
Multiple Choice QuestionsIf the critical angle for total internal reflection from a medium to vacuum is 30°, the velocity of light in the medium is :
3 × 108 m/s
1.5 × 108 m/s
6 × 108 m/s
× 108 m/s
The refractive index of the material of the prism and liquid are 1.56 and 1.32 respectively. What will be the value of θ for the following refraction?
A transparent cube of 15 cm edge contains a small air bubble. Its apparent depth, when viewed through one face, is 6 cm and when viewed through the opposite face is 4 cm. Then the refractive index of the material of the cube is:
2.0
2.5
1.6
1.5
For a telescope, larger be the diameter of the objective lens:
greater the resolving power
smaller is the resolving power
greater is the magnifying power
smaller is the magnifying power
In the given figure, what is the angle of the prism?
A
B
C
D
The deviation is maximum for which colour :
Violet
Red
Blue
Green
A prism of refractive index √2 has a refracting angle of 60°. At what angle a ray must be incident on it so that it suffers a minimum deviation?
45°
60°
90°
180°
A person who can see things most clearly at a distance of 10 cm, requires spectacles to enable to see clearly things at a distance of 30 cm. What should be the focal length of the spectacles?
15 cm (concave)
15 cm (convex)
10 cm (concave)
0
A light wave travels from glass to water. The refractive indices for glass and water are and respectively. The value of the critical angle will be :
The radius of the convex surface of the plano-convex lens is 20 cm and the refractive index of the material of the lens is 1.5. The focal length is :
30 cm
50 cm
20 cm
40 cm
