Class 10 Light Reflection And Refraction CBSE Questions & Answers

Class 10 · Light Reflection And Refraction

Class 10 Light–Reflection and Refraction CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
The magnification of plane mirror is
  • A
    Infinite
  • B
    2.0
  • C
    1.0
    Correct
  • D
    0.0
2
Virtual, erect and diminished size image are the characteristic features of a
  • A
    convex mirror
    Correct
  • B
    plane mirror
  • C
    concave mirror
  • D
    Biconcave mirror
3
How does the frequency of a beam of ultra-violet light change when it goes from air into glass
  • A
    remains the same
  • B
    None of these
  • C
    frequency decreases
    Correct
  • D
    frequency increases
4
Where will the image be if the object is at focus of the concave mirror?
  • A
    beyond C
  • B
    at C
  • C
    Between C and F
  • D
    Infinity
    Correct
5
A convex lens has a focal length of 40 cm. calculate its power
  • A
    2.5 D
    Correct
  • B
    6.6D
  • C
    3.5 D
  • D
    4.5 D
6
According to snell’s law , \({{\rm{n}}_{{\rm{21}}}} \times {{\rm{n}}_{{\rm{12}}}}\) = ?
  • A
    2.0
  • B
    0.0
  • C
    1.0
    Correct
  • D
    \({1 \over 2}\)
7
A convex lens is-
  • A
    Called diverging lens.
  • B
    Thicker at the edges than at middle.
  • C
    Of uniform thickness everywhere.
  • D
    Thicker at the middle than at edges.
    Correct
8
Which type of mirror is used in ophthalmoscope to examine throat and ear?
  • A
    plane mirror
  • B
    concave
    Correct
  • C
    convex
  • D
    reflecting mirror
9
If the angle of incidence is \({\rm{9}}{0^0}\) , What is the angle of refraction?
  • A
    sin-1 \(\left( {{1 \over n}} \right)\)
    Correct
  • B
    r = \(\underline 1 \)
  • C
    r = \({\rm{9}}{0^0}\)
  • D
    r = 45
10
What is the value of speed of light in free space?
  • A
    \({\rm{3}} \times {\rm{1}}{0^{\rm{6}}}\) m/s
  • B
    \({\rm{3}} \times {\rm{1}}{0^{\rm{5}}}\) km/s
    Correct
  • C
    \({\rm{3}} \times {\rm{1}}{0^{\rm{8}}}\) km/s
  • D
    \({\rm{3}} \times {\rm{1}}{0^{\rm{5}}}\) m/s
11
When two prism, one up and one down in contact receives white, What colour of light will cmerge out?
  • A
    Green colour
  • B
    white colour
    Correct
  • C
    Blue colour
  • D
    red colour
12
What colour we get while mixing Blue with green?
  • A
    Black
  • B
    cyan
    Correct
  • C
    Yellow
  • D
    Pink
13
Which colour has the greatest speed in the visible region?
  • A
    orange
  • B
    red
  • C
    Green
  • D
    violet
    Correct
14
If f1 and f2 are the focal lengths of two lenses, what is the relation for equivalent focal length?
  • A
    \({{{f_1} \times {f_2}} \over {{f_1} + {f_2}}}\)
  • B
    \({{2\left( {{f_1} + {f_2}} \right)} \over {2{f_1} \times {f_2}}}\)
  • C
    \({{{f_1} + {f_2}} \over {f1f2}}\)
    Correct
  • D
    \({{2{f_1} \times {f_2}} \over {{f_1} + {f_2}}}\)
15
In what direction, the ray of light bends as it travels from denser to rarer medium
  • A
    None of these
  • B
    bends away from the normal
    Correct
  • C
    doesn’t bend at all
  • D
    bends towards the normal