M.C.Q : Ray Optics

LEVEL – I

1. If the behavior of light rays through a convex lens is as shown in the adjoining figure, then;

(A) μ = μ2

(B) μ < μ2

(C) μ > μ2

(D) μ ≤ μ2

2. A ray of light is incident at the glass-water interface at an angle i , it emerges finally parallel to the surface of water, then the value of μg would be

(A) (4/3)sin(i)

(B) [1/sin(i)]

(C) 4/3

(D) 1

1. A converging lens is used to form an image on a screen. When the upper half of the lens is covered by an opaque screen :

(A) half of the image will disappear

(B) image will not form on the screen.

(C) intensity of image will increase

(D) intensity of image will decrease

1. A spherical convex surface separates object and image space of refractive index 1 and 4/3 respectively. If radius of curvature of the surface is 0.1 m, its power is :

(A) 2.5 D

(B) -2.5 D

(C) 3.3 D

(D) -3.3 D

1. A ray of light passes through an equilateral prism such that the angle of incidence is equal to the angle of emergence and latter is equal to 3/4th the angle of prism. The angle of deviation is :

(A) 45o

(B) 39o

(C) 20o

(D) 30o

6.A liquid is placed in a hollow prism of angle 60o. If angle of the minimum deviation is 30o, what is the refractive index of the liquid?

(A) 1.41

(B) 1.50

(C) 1.65

(D) 1.95

7. A prism can produce a minimum deviation d in a light beam. If three such prisms are combined, the minimum deviation that can be produced in this beam is:

(A) 0

(B) δ

(C) 2δ

(D) 3δ

8. The face PR of a prism QPR of angle 30o is silvered. A ray is incident on face PQ at an angle of 45o as shown in figure. The refracted ray undergoes reflection on face PR and retraces its path. The refractive index of the prism is :

(A) Ö2

(B) 3/Ö2

(C) 1.5

(D) 1.33

9. A particle moves towards a concave mirror of focal length 30 cm along its axis and with a constant speed of 4 cm/ sec. What is the speed of its image when the particle is at 90 cm from the mirror?

(A) 2 cm/ sec.

(B) 8 cm/sec.

(C) 1 cm/sec.

(D) 4 cm/sec.

10.A thin prism of glass is placed in air and water successively. If aμg = 3/2 and aμw = 4/3, then the ratio of deviations produced by the prism for a small angle of incidence when placed in air and water is :

(A) 9 : 8

(B) 4 : 3

(C) 3 : 4

(D) 4 : 1

11. A thin prism P1 with angle 4o and made from glass of refractive index 1.54 is combined with another thin prism P2 made from glass of refractive index 1.72 to produce dispersion without deviation. The angle of the prism P2 is :

(A) 5.33o

(B) 4o

(C) 3o

(D) 2.6o