Class 10 Human Eye And Colourful World CBSE Questions & Answers

Class 10 · Human Eye And Colourful World

Class 10 Human Eye and Colourful World CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Which is the correct condition for the total internal reflection to occur?
  • A
    All of these
  • B
    light should pass from rarer to denser medium
  • C
    light should pass from denser to rarer medium
    Correct
  • D
    Critical angle should be grater than angle of incidence
2
If the angle of incidence is increased for a pair of air – glass interface, then the angle of refraction will
  • A
    remains the same
  • B
    decrease
    Correct
  • C
    increase
  • D
    first increases and then decreases
3
The lateral displacement of an incident ray passing out of a rectangular glass slab
  • A
    None of these
  • B
    is directly proportional to the thickness of the glass slab
    Correct
  • C
    independent of the thickness of the glass slab
  • D
    inversely proportional to the thickness of the glass slab
4
Find the incorrect statement
  • A
    Large sized particles scatter light of longer wavelengths
  • B
    Presbyopia occurs due to weakening of ciliary muscles
  • C
    Refractive index of glass for violet colour is more than that for red colour
  • D
    Sun is visible 2 minutes after sunrise and 2 minutes before sunset
    Correct
5
A person developing near sightedness due to-
  • A
    All of these
    Correct
  • B
    The size of eye ball has elongated
  • C
    The focal length of eye lens has decreased
  • D
    Power of eye lens has increased
6
Which of the following phenomena is not the result of total internal reflection?
  • A
    Mirage
  • B
    Twinkling of stars
  • C
    both Looming and Twinkling of stars
    Correct
  • D
    Looming
7
Danger signals are red in colour because
  • A
    red colour is least scattered
    Correct
  • B
    wavelength of red colour is less than that of other colour
  • C
    red colour looks attractive
  • D
    red colours is most scattered
8
Optical fibre is used for
  • A
    All of these
    Correct
  • B
    biomedical engineering
  • C
    medical applications
  • D
    communication over long distance
9
A person cannot see distinctly any object placed beyond 40cm from his eyes. Calculate the power of the lens which will help him to see distant objects clearly.
  • A
    -1.5 Dioptre
  • B
    -2.5 Dioptre
    Correct
  • C
    +1 Dioptre
  • D
    +2 Dioptre
10
Bees are sensitive to
  • A
    Infrared light
  • B
    ultraviolet red
    Correct
  • C
    All of these
  • D
    White light
11
Statement A : Improper functioning of rod shaped cells causes colour blindness , Statement B : The focal length of the human eye can be increased or decreased
  • A
    Both Statement A and B are true
  • B
    Neither statement A nor statement B is true
  • C
    Statement A is true, B is false
  • D
    Statement B is true, A is false
    Correct
12
A boy uses spectacles of focal length – 50cm. Hence the defect of vision, he is suffering from-
  • A
    Far-sightedness
  • B
    Myopia
    Correct
  • C
    Presbyopia.
  • D
    Hypermetropia
13
What happens to the image distance in the eye when we increase the distance of an object from the eye?
  • A
    Image distance increases
  • B
    first increases then decreases
  • C
    Image distance decreases
  • D
    remains the same
    Correct
14
The near point of a hypermetropic person is 75 cm if the person uses eye glasses having power +1.0D, Calculate the distance of distinct vision for him?
  • A
    +400cm
  • B
    +300cm
  • C
    -400cm
  • D
    -300cm
    Correct
15
What is the value of refractive index of the medium if the critical angle of incidence in a denser – rarer inter face is equal to \({\rm{4}}{{\rm{5}}^0}\) ?
  • A
    2.414
  • B
    3.25
  • C
    1.414
    Correct
  • D
    2.0