Light Class 8 MCQs Questions with Answers
I. Choose the correct option.
Question 1.
We are able to see an object due to the presence of
(a) light
(b) dark
(c) refraction
(d) object
Answer
Answer: (a) light
Question 2.
The bouncing back of light into the same medium is called
(a) refraction
(b) reflection
(c) dispersion
(d) diffraction
Answer
Answer: (b) reflection
Question 3.
A mirror has ____ surface.
(a) rough
(b) polished
(c) dark
(d) all of these
Answer
Answer: (b) polished
Question 4.
Maximum part of light is reflected by
(a) opaque object
(b) translucent object
(c) transparent object
(d) all of these
Answer
Answer: (a) opaque object
Question 5.
Beam of light striking the reflecting surface is called
(a) incident ray
(b) reflected ray
(c) refracted ray
(d) normal ray
Answer
Answer: (a) incident ray
Question 6.
The back side of a plane mirror contains
(a) gold coating
(b) silver coating
(c) aluminium coating
(d) copper coating
Answer
Answer: (b) silver coating
Question 7.
The perpendicular drawn to the reflecting surface is called
(a) normal
(b) incident ray
(c) reflected ray
(d) none of these
Answer
Answer: (a) normal
Question 8.
There are _______ laws of reflection.
(a) one
(b) two
(c) three
(d) four
Answer
Answer: (b) two
Question 9.
The angle of incidence is always _______ to the angle of reflection.
(a) greater
(b) smaller
(c) equal
(d) none of these
Answer
Answer: (c) equal
Question 10.
The angle between the reflected ray and the normal is called
(a) angle of incidence
(b) reflected ray
(c) angle of reflection
(d) point of incidence
Answer
Answer: (c) angle of reflection
Question 11.
The reflection of light from a smooth surface is called
(a) diffused reflection
(b) regular reflection
(c) dispersion
(d) spectrum
Answer
Answer: (b) regular reflection
Question 12.
Which of the following results in diffused reflection?
(a) Plane mirror
(b) Shiny surface
(c) Silver
(d) Wood
Answer
Answer: (d) Wood
Question 13.
The nature of image formed by plane mirror is
(a) real and inverted
(b) virtual and erect
(c) real and erect
(d) virtual and inverted
Answer
Answer: (b) virtual and erect
Question 14.
If you hold a pen in your right hand and stand in front of the mirror, the pen will be in the left hand in the image. This phenomenon is called
(a) lateral inversion
(b) diffraction
(c) reflection
(d) inversion
Answer
Answer: (a) lateral inversion
Question 15.
If two plane mirrors are inclined at an angle of 40°, number of images formed will be
(a) 7
(b) 8
(c) 9
(d) 5
Answer
Answer: (b) 8
Question 16.
Type of mirror used as side view mirror is
(a) convex mirror
(b) plane mirror
(c) concave mirror
(d) ground mirror
Answer
Answer: (a) convex mirror
Question 17.
Band of seven colours is called
(a) VIBGYOR
(b) dispersion
(c) spectrum
(d) reflection
Answer
Answer: (c) spectrum
Question 18.
Front bulged part of the eyeball is called
(a) cornea
(b) iris
(c) retina
(d) pupil
Answer
Answer: (a) cornea
Question 19.
Two mirrors A and B are placed at right angles to each other. A ray of light incident on mirror A at an angle of 25° falls on mirror B after reflection. The angle of reflection for the ray reflected from mirror B would be
(a) 25°
(b) 50°
(c) 65°
(d) 115°
Answer
Answer: (c) 65°
Question 20.
Visually impaired people can read and write using
(a) electronic writer
(b) Braille system
(c) digital pens
(d) hearing aids
Answer
Answer: (b) Braille system
II. Fill in the blanks with suitable word/s.
Question 1.
Light is a form of __________
Answer
Answer: energy
Question 2.
The ray of light which strikes the reflecting surface is called __________ ray.
Answer
Answer: incident
Question 3.
The bouncing back of light after it falls on a surface is called __________
Answer
Answer: reflection
Question 4.
A mirror has _________ and _________ surface.
Answer
Answer: smooth, polished
Question 5.
__________ is the perpendicular line on the incidence point.
Answer
Answer: Normal
Question 6.
A plane mirror forms a _________ image.
Answer
Answer: virtual
Question 7.
The ray which returns after striking the surface is called __________ ray.
Answer
Answer: reflected
Question 8.
Angle of incidence is always __________ to the angle of reflection.
Answer
Answer: equal
Question 9.
Reflection from a smooth surface is called __________ reflection.
Answer
Answer: regular
Question 10.
The size of image formed by the plane mirror is __________ as size of object.
Answer
Answer: same
Question 11.
Splitting of light into seven colours is called __________
Answer
Answer: dispersion
Question 12.
Kaleidoscope is based on the concepts of __________
Answer
Answer: multiple reflection
Question 13.
The point on the surface at which incident ray strikes is called __________
Answer
Answer: point of incidence
Question 14.
The reflection of light from an uneven surface is called __________
Answer
Answer: diffused reflection
Question 15.
Paper is a _________ surface.
Answer
Answer: rough
Question 16.
Mirror is a __________ surface.
Answer
Answer: smooth
Question 17.
When the mirrors are inclined at 90°, we get __________ images.
Answer
Answer: three
Question 18.
In bright light, the size of pupil __________
Answer
Answer: decreases
Question 19.
The space between the cornea and lens is filled with a liquid called __________
Answer
Answer: aqueous humour
Question 20.
Braille system was invented by __________
Answer
Answer: Louis Braille
III. True or False
Question 1.
Deficiency of vitamin B causes night blindness.
Answer
Answer: False
Question 2.
In the Braille system, patterns are made with coloured dots.
Answer
Answer: False
Question 3.
Normal make 60° angle with the reflecting surface.
Answer
Answer: False
Question 4.
Angle of incidence is always equal to angle of reflection.
Answer
Answer: True
Question 5.
Diffused reflection occurs due to rough surface.
Answer
Answer: True
Question 6.
Kaleidoscope is based on the principle of dispersion of light.
Answer
Answer: False
Question 7.
Both incident ray and reflected ray lie in the same plane.
Answer
Answer: True
Question 8.
The choroid prevents the internal reflection of light and protects the light sensitive inner parts of the eye.
Answer
Answer: True
Question 9.
Rainbow forms due to dispersion.
Answer
Answer: True
Question 10.
Rods are sensitive to bright light.
Answer
Answer: False
Question 11.
The iris is the coloured part of the eye.
Answer
Answer: True
Question 12.
Diffused reflection is due to the failure of laws of reflection.
Answer
Answer: False
Question 13.
Ciliary muscles changes the shape of the lens in the eye.
Answer
Answer: True
Question 14.
We should not wash our eyes.
Answer
Answer: False
Question 15.
Braille was designed by Louis Braille.
Answer
Answer: True
IV. Match the following
| Column I | Column II |
| 1. Reflection | (a) Regular reflection |
| 2. Normal vision | (b) bouncing back of light |
| 3. Smooth surface | (c) 25 cm |
| 4. Kaleidoscope | (d) Short-sightedness |
| 5. Hypermetropia | (e) Dispersion of light |
| 6. Cornea | (f) For visually challenged person |
| 7. Rainbow | (g) Multiple images |
| 8. Blind spot | (h) Front part of the eye |
| 9. Braille system | (i) Sensitive for bright light |
| 10. Rods | (j) Long-sightedness |
| 11. Cones | (k) Sensitive for dim light |
| 12. Myopia | (l) No sensory nerves |
| 13. Retina | (m) Cataract |
| 14. Cloudy lens | (n) Ability to focus |
| 15. Accommodation power | (o) Image formed |
Answer
Answer:
| Column I | Column II |
| 1. Reflection | (b) bouncing back of light |
| 2. Normal vision | (c) 25 cm |
| 3. Smooth surface | (a) Regular reflection |
| 4. Kaleidoscope | (g) Multiple images |
| 5. Hypermetropia | (j) Long-sightedness |
| 6. Cornea | (h) Front part of the eye |
| 7. Rainbow | (e) Dispersion of light |
| 8. Blind spot | (l) No sensory nerves |
| 9. Braille system | (f) For visually challenged person |
| 10. Rods | (k) Sensitive for dim light |
| 11. Cones | (i) Sensitive for bright light |
| 12. Myopia | (d) Short-sightedness |
| 13. Retina | (o) Image formed |
| 14. Cloudy lens | (m) Cataract |
| 15. Accommodation power | (n) Ability to focus |
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