31
A light beam that appears at the main focus of a concave lens will emit after refraction.
A)
parallel to the principal axis
B)
through the main focus
C)
without any deviation
D)
through the center of curvature
Answer & Solution
Answer: Option
A
32
The focal length of a spherical mirror is . . . . . . . .
A)
double its radius of curvature
B)
three times its radius of curvature
C)
half of its radius of curvature
D)
its radius of curvature
Answer & Solution
Answer: Option
C
33
Two glass lenses of same focal length, one being convex and the other concave, are kept in contact, the combination will act as
A)
convergent lens
B)
divergent lens
C)
plane glass sheet
D)
mirror
Answer & Solution
Answer: Option
C
34
Which of the following does not used concave mirror?
A)
search light
B)
solar furnace
C)
rearview mirror
D)
car headlight
Answer & Solution
Answer: Option
C
35
The theory belongs behind stars twinkling is that-
A)
The refractive index of the different layers of earth's atmosphere changes continuously, consequently the position of the star's image changes with time
B)
The intensity of light emitted by them changes with time
C)
The light from the star is scattered by the dust particles and air molecules in the earth's atmosphere
D)
The distance of the stars from the earth changes with time
Answer & Solution
Answer: Option
A
36
Persons suffering from myopia are advised to use
A)
convex lens
B)
concave lens
C)
plano-convex lens
D)
plano-concave lens
Answer & Solution
Answer: Option
B
37
The characteristics of an image form by a plane mirror are:
A)
same size, erect, lateral inverted, virtual
B)
same size, erect, inverted, real, magnified
C)
different shape, erect, inverted, virtual
D)
different size, magnified, inverted virtual
Answer & Solution
Answer: Option
A
38
In which case a incident ray and reflected ray are all on the same surface?
A)
in case of incidence angle
B)
both refraction and reflection
C)
electric potential energy
D)
amplification of refractive index
Answer & Solution
Answer: Option
B
39
The center of the reflecting surface of a spherical mirror of a point called.
A)
Center of Curvature
B)
Pole
C)
Focus
D)
Principal axis
Answer & Solution
Answer: Option
B
40
Which one of the following energy conversions takes place in carrying out the process of photosynthesis?
A)
Light to chemical energy
B)
Light to thermal energy
C)
Thermal to biochemical energy
D)
Heat to kinetic energy
Answer & Solution
Answer: Option
A
