Light reflection and refraction Worksheet-28

Light reflection and refraction Worksheet-28

61. The value of refractive index ‘n’ for the given refraction is:

A. > 1                                               B. < 1

C. = 1                                               D. Data insufficient

62. For the given ray diagrams, which of the following statement is true

A. n₁ = n₂ and n₃ > n₄                                  B. n₁ > n₂ and n₃ > n₄

C. n₁ = n₂ and n₃ < n₄                                  D. n₁ = n₂ and n₃ = n₄

63. Which of the following ray diagram is correct if student is finding focal length by focusing distanT object?

A.

B.

C.

D.

64. Angle of incidence = Angle of reflection. It is true for

A. Only plane mirror

B. Both mirrors as well as lens

C. Both plane mirror and spherical mirror

D. Only for lenses

65. Image formed by plane mirror is

A. Real

B. Virtual

C. Real or virtual depending on its distance from mirror

D. Inverted

66. An object is placed before convex lens. The image  formed is

A. Real only                                   B. erect and virtual

C. May be real or virtual             D. inverted

67. A convex lens is

A. Thicker at the middle than at the edges

B. Thicker at the edge than at middle

C. Of uniform thickness everywhere

D. Called diverging lens

68. An incident ray passes through the centre of curvature of a spherical mirror, the reflected ray will

A. Pass through the pole             B. pass through the focus

C. retrace its path                         D. be parallel to principal axis

69. If ‘f’ is focal length and ‘r’ is radius of curvature, then is valid for

A. Convex mirror but not for concave mirror

B. Concave mirror only

C. Both convex and concave mirror

D. Concave lens only 

70. A student is finding a focal length of the concave mirror by focusing a distant object. He chose wall as screen. If the distance between the wall and the mirror is 10 cm then focal length of mirror is

A. 20 cm                                         B. 5 cm

C. 10 cm                                         D. can’t be determined

Answer Key:

61. B
62. A
63. A
64. C
65. B
66. C
67. A
68. C
69. C
70. C