CBSE Class 8 Science Light Assignment

Read and download free pdf of CBSE Class 8 Science Light Assignment. Get printable school Assignments for Class 8 Science. Class 8 students should practise questions and answers given here for Chapter 16 Light Science in Class 8 which will help them to strengthen their understanding of all important topics. Students should also download free pdf of Printable Worksheets for Class 8 Science prepared as per the latest books and syllabus issued by NCERT, CBSE, KVS and do problems daily to score better marks in tests and examinations

Assignment for Class 8 Science Chapter 16 Light

Class 8 Science students should refer to the following printable assignment in Pdf for Chapter 16 Light in Class 8. This test paper with questions and answers for Class 8 Science will be very useful for exams and help you to score good marks

Chapter 16 Light Class 8 Science Assignment

Question 1. Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room. Explain.

Answer- We can see objects only if light from any source enter our eyes. If we are in a dark room, then it is not possible for us to see objects in the room. However, if there is light outside the room, then objects outside the room are visible to us.
 
Question 2. Differentiate between regular and diffused reflection. Does diffused reflection mean the failure of the laws of reflection?
Answer-
                       Regular Reflection                             Diffused Reflection
1. It occurs from shiny and smooth surface.        1. It occurs from unpolished and rough surfaces.
2. Reflected rays are parallel to each other.         2. Reflected rays are parallel not to each other
The laws of reflection have not failed even in diffused reflection, because each ray obeys the law of reflection.
 
Question 3. Mention against each of the following whether regular or diffused reflection will take place when a beam of light strikes. Justify your answer in each case.
 
(a) Polished wooden table.
Answer- Regular reflection will take place as the surface is smooth.
 
(b) Chalk powder.
Answer- Diffused reflection will take place as the surface is not smooth.
 
(c) Cardboard surface.
Answer- Diffused reflection will take place as the surface is not smooth.
 
(d) Marble floor with water spread over it.
Answer- Regular reflection will take place as the surface is smooth.
 
(e) Mirror.
Answer- Regular reflection will take place as the surface is smooth.
 
(f) Piece of paper.
Answer- Diffused reflection will take place as the surface is not smooth.
 
Question 4. State the laws of reflection.
Answer- Laws of reflection:
(i) The angle of reflection is always equal to the angle of incidence.
(ii) The incident ray, the reflected ray and the normal at the point of incidence, all lie in the same plane.
 
Question 5. Describe an activity to show that the incident ray, the reflected ray and the normal at the point of incidence lie in the same plane.
Answer- Fix a white sheet of paper on a drawing board or a table. Let the sheet project a little beyond the edge of the table. Make a ray of light by passing torch light through a comb with all its openings closed except one in the middle. Place a strip of plane mirror in the path of the light ray. After striking the mirror, the ray of light is reflected in another direction. This is called the reflected ray. Now, cut the projecting portion of the sheet in the middle. Look at the reflected ray. Bend that part of the projected portion on which the reflected ray falls. The reflected ray that fell along this part can no longer be seen. This shows that the incident ray, the reflected ray and the normal at the point of incidence lie in the same plane.
 
Question 6- Fill in the blanks in the following.
(a) A person 1 m in front of a plane mirror seems to be 2 m away from his image.
(b) If you touch your left ear with right hand in front of a plane mirror it will be seen in the mirror that your right ear is touched with left hand.
(c) The size of the pupil becomes large when you see in dim light.
(d) Night birds have less cones than rods in their eyes.
 
Choose the correct option in Questions 7 – 8
 
Question 7. Angle of incidence is equal to the angle of reflection.
(a) Always (✓)
(b) Sometimes
(c) Under special conditions
(d) Never
 
Question 8. Image formed by a plane mirror is:
(a) virtual, behind the mirror and enlarged.
(b) virtual, behind the mirror and of the same size as the object. (✓)
(c) real at the surface of the mirror and enlarged.
(d) real, behind the mirror and of the same size as the object.
 
Question 9. Describe the construction of a kaleidoscope.
Answer- Take three rectangular mirror strips of dimensions 15cm x 4cm and join them together to form a prism. A prism is fixed into a circular cardboard tube. This circular tube is now closed at one end with a cardboard disc. This disc has a hole through which we can see. At the other end of the circular tube, a plane glass plate is fixed. On this glass plate, several small and broken pieces of coloured glass are placed. This end is now closed by a round glass plate allowing enough space for the coloured glass pieces to move.
8th.sci.eng.july.aug 6
Question 10- Draw a labelled sketch of the human eye.
Answer-
8th.sci.eng.july.aug 7
 
Question 11. Gurmit wanted to perform Activity 16.8 using a laser torch. Her teacher advised her not to do so. Can you explain the basis of the teacher’s advise?
Answer- Because of the intensity of the laser light is very high, and it is harmful to the human eyes. It can cause damage to the retina and leads to blindness.
 
Question 12- Explain how you can take care of your eyes.
Answer- (i) Visit an eye specialist regularly.
(ii) Avoid reading in dim light and very bright light.
(iii) Avoid direct exposure of sunlight to the eye.
(iv) Clean your eyes with cold water quickly if dust particles or small insects enter your eye.
(v) Do not rub your eyes.
(vi) Maintain a distance of at least 25 cm between the book and your eyes while reading.
 
Question 13- What is the angle of incidence of a ray if the reflected ray is at an angle of 90° to the incident ray?
Answer- 45º.
 
Question 14- How many images of a candle will be formed if it is placed between two parallel plane mirrors separated by 40 cm?
Answer- Infinite number of images.
 
Question 15- Two mirrors meet at right angles. A ray of light is incident on one at an angle of 30° as shown in Fig. 16.19. Draw the reflected ray from the second mirror.
 
8th.sci.eng.july.aug 8
Question 16- Boojho stands at A just on the side of a plane mirror as shown in Fig. 16.20. Can he see himself in the mirror? Also can he see the image of objects situated at P, Q and R?
 
8th.sci.eng.july.aug 9
Answer- A plane mirror forms a virtual image at same distance behind the mirror. A cannot see his image because the length of the mirror is too short on his side. However, he can see the objects placed at points P and Q, but cannot see the object placed at point R as shown in figure.
 
Question 17- (a) Find out the position of the image of an object situated at A in the plane mirror (Fig. 16.21).
(b) Can Paheli at B see this image?
(c) Can Boojho at C see this image?
(d) When Paheli moves from B to C, where does the image of A move?
8th.sci.eng.july.aug 10
Answer-
a) Image of an object placed at A is formed behind the mirror at the same distance.
b) Yes Paheli at B can see this image.
c) Yes Boojho at C can see this image.
d) Image of the object at A will not move.
 
 
More Question-

 CBSE Class 8 Science - Light (1)

CBSE Class 8 Science - Light (1)

CBSE Class 8 Science - Light (1)

1. Draw a diagram to show the reflection of light from a plane mirror. Label the following on the diagram:

(a) Plane mirror (b) Incident ray (c) Reflected ray

(d) Point of incidence (e) Normal (f) Angle of incidence

(e) Angle of reflection.

2. How many reflected rays can there be for a given single incident ray falling on a plane mirror?

3. State the Laws of Reflection of Light.

4. An incident ray makes an angle of 750 with the surface of a plane mirror. What will be the angle of reflection?

5 A ray of light is incident normally {perpendicularly} on a plane mirror. Where will this ray of light go after reflection from the mirror ?

6 What is the difference between regular reflection and diffuse reflection of light ?

7 State whether the following statement is true or false :

Diffuse reflection means the failure of the laws of reflection of light.

8 Draw a labeled diagram showing how a plane mirror forms an image of a point object placed in front of it.

9 If an object is placed at a distance of 7.5 cm from a plane mirror, how far would it be from its image ?

10 You see your image in a plane mirror? State two characteristics of the image so formed.

11 Name the phenomenon responsible for the following effect:

When we sit in front of a plane mirror and write with our right hand, it appears in the mirror that we are writing with the left hand.

 12 Fill in the following blanks:

 If you touch your------ ear with right hand in front of a plane mirror, it will be seen in the mirror that your right ear is touched with -------

13 How are the two plane mirrors in a periscope arranged?

 With respect to one another?

 With respect to sides of the tube?

14 Explain how, a hair dresser makes you see hair at the back of your head after the hair cut is complete.

15 How many images of an object will be formed when the object is placed between two plane mirrors which are inclined at the following angles to one another?

(a) 120° (b) 45° (c)180° (d) 60° (e) 90°

16 What will be the number of images formed when an object is placed between two parallel plane mirrors facing each other?

17 Describe the construction of a kaleidoscope.

18 How many plane mirror strips are there in a kaleidoscope? How are they arranged?

19 State one use of kaleidoscope.

20 What is meant by “dispersion of light “? Name a natural phenomenon which is caused by the dispersion of sunlight in the sky.

21. What are the functions of the following parts of the eye?

(a) Iris (b) Ciliary muscles (c) Retina (d) optic nerve.

22 Name the cells on the retina of an eye:

(a) which are sensitive to bright light.

(b) which are sensitive to dim light.

(c) which produces sensation of colours.

23. Explain why, we cannot see our surroundings clearly when we enter a darkened cinema hall from bright sunshine but our vision improves after sometime.

24. What happens to the size of the pupil of our eye:

(a) in dim light?

(b) in bright light?

25. What is the range of vision of a normal human eye?

26. Name the phenomenon which enables us to see movies in cinema hall.

27. What is meant by ‘persistence of vision’?

28 What are the various defects of eye? Explain them in brief? Also suggest the corrective measures of the defects.

Q.1. Complete the following sentences

a) The coloured, disc shaped diaphragm in the eye is called the …………..

b) In regular reflection, the reflected rays remain ……………. to each other.

c) The number of image is infinite when the angle between the mirrors is …………….

Q.2.Name the following

a) Light of all colours are mixed in a certain proportion.

b) Blindness arising out of lack of Vitamin A in the diet.

c) The rays of beam are reflected in different directions.

d) A protective white membrane covering most of the eye ball.

Q.3.Define the following terms

a) Braille

b) Lateral Inversion

c) Kaleidoscope

d) Dispersion

e) Spectrum

f) Accommodation

g) Cataract

Q.4.Differentiate between the following

b) Reflection and Refraction

c) Myopia and hypermetropia

Q.5.Give reasons for the following

a) A shiny metal utensil forms an image, but the image is not clear as that formed by a mirror.

b) You see a clear, bright image of an object in a mirror.

c) When a mirror is held behind your head after a haircut, not only you see the back of your head, you also see innumerable images of yourself.

Q.6.Answer the following in not more than 20 words.

b. What happens to the rays of light in case of diffuse reflection?

c. An object is placed 20 cm in front of a plane mirror. Where is the image formed? How far is it from the mirror?

d. An object is placed between two mirrors that are at 60° to each other. How many images are formed?

Q.7.Answer the following in not more than 40 words.

a. State the laws of reflection of light.

b. What do you understand by the blind spot of the eye?

Q.8.Answer the following in not more than 100 words.

a. What vision related problems occur when the diet lacks Vitamin A?

b. Describe the structure of the eye with the help of a diagram.

1.Light is a form of ___________ radiation.
(A) Electromagnetic.
(B) Mechanical.
(C) Longitudinal.
(D) None of these.

2.The wavelength of visible light is in the range:
(A) 4 × 10-7 m to 8 × 10-7 m.
(B) 4 × 107 m to 8 × 107 m.
(C) 4 × 103 m to 8 × 103 m.
(D) None of these.

3.An ________ image can be obtained on a screen.
(A) Real.
(B) Virtual.
(C) Upright.
(D) Inverted.

4.According to the laws of reflection:
(A) Angle i = Angle r
(B) Sine i = sine r
(C) Sine i / Sine r = constant
(D) All of these.

5.The colour of an object is determined by
(A) The colour of light reflected by it:
(B) The colour of light absorbed by it.
(C) The colour of light incident on it only.
(D) None of the above.

6.Human eye is one of the most valuable and sensitive organ that:
(A) Enables us to see the wonderful world and colours around us.
(B) Can identify the objects.
(C) Is like a camera.
(D) All of these.

7.The ray of light strikes at the surface of mirror is called:
(A) Reflected ray.
(B) Incident ray.
(C) Normal ray.
(D) None of these.

8.Which of the following does not describe working of the human eye?
(A) Light enters the eye through a thin membrane called the cornea.
(B) Rainbow is formed due to splitting of white light.
(C) Iris is a dark muscular diaphragm that controls the size of the pupil for.
(D) Regulating the amount of light entering into the eye.

9.Electrical signals generated by light sensitive cells of retina are sent to the brain via:
(A) Motor nerves.
(B) Optic nerves.
(C) Sensory nerves.
(D) Spinal cord.

10.Least distance of vision for a normal eye is:
(A) 25 cm.
(B) 1 m.
(C) 30 cm.
(D) Infinity.

11.The eye lens forms an ___________ and _________ image of the object on the retina.
(A) Virtual and erect.
(B) Real and inverted.
(C) Real and erect.
(D) Virtual and erect.

12.Iris contracts the pupil:
(A) In bright light.
(B) To allow less light to enter.
(C) In darkness.
(D) Only (a) and (b).

13.Colour blindness is the name given to:
(A) Inability to distinguish between colours.
(B) Inability to see anything.
(C) Inability to see in dark.
(D) Inability to see in bright light.

14.The transparent front part of eye is called:
(A) Iris.
(B) Cornea.
(C) Pupil.
(D) Cone.

15.Reflection from a rough surface is called:
(A) Regular reflection.
(B) Diffused reflection.
(C) Irregular reflection.
(D) Only (b) & (c).

16.Reflection from a smooth surface is called:
(A) Regular reflection.
(B) Diffused reflection.
(C) Irregular reflection.
(D) None of these.

17.If angle of incidence is 30° than angle of reflection will be
(A) 60°
(B) 0°
(C) 30°
(D) None.

18.If the angle between incident and reflected ray is 50° than find the angle of incidence.
(A) 50°
(B) 30°
(C) 25°
(D) 100°

19.Splitting of white light on passage through a triangular prism:
(A) Takes place due to the inclined surfaces.
(B) Is known as dispersion of light.
(C) Is into a band of seven colours known as spectrum.
(D) All of these.

20.What is the angle of incidence of a ray if the reflected ray is at an angle of 90° to the incident ray?
(A) 500
(B) 600
(C) 450
(D) 900

21.The image formed by plane mirror is:
(A) Erect.
(B) Upside.
(C) Real.
(D) All of these.

22.The size of image formed by the plane mirror is………….the size of object.
(A) smaller than
(B) bigger than
(C) equal to
(D) None.

23.Splitting of white light into seven colours is known as:
(A) Dispersion.
(B) Reflection.
(C) Refraction.
(D) None of these.

24.Cataract is a condition:
(A) When the crystalline lens becomes milky and cloudy.
(B) That may cause partial or complete loss of vision.
(C) That can be rectified through a cataract surgery.
(D) All of these.

25.The angle between incident ray and normal is known as:
(A) angle of reflection.
(B) angle of incidence.
(C) angle of refraction.
(D) None of these.

26.The angle between reflected ray and normal is known as:
(A) angle of reflection.
(B) angle of incidence.
(C) angle of refraction.
(D) None of these.

27.The line at right angle to the mirror surface at the point of incidence is called:
(A) Incidence ray.
(B) Reflected ray.
(C) Normal.
(D) None.

28.If an object is placed at a distance of 8 cm in front of a plane mirror, how far its image will form from the mirror?
(A) 16 cm.
(B) 8 cm.
(C) 4 cm.
(D) 10 cm.

29.If an object is placed at a distance of 10 cm in front of a plane mirror, how far would it be from its image?
(A) 16 cm.
(B) 20 cm.
(C) 14 cm.
(D) 10 cm.

30.If the distance between the object and its image in a plane mirror is 14.6 cm, how far is the object from the mirror?
(A) 14.6 cm.
(B) 7.3 cm.
(C) 29.2 cm.
(D) None of these.

31.The image formed in a plane mirror is sideways reversed. This phenomenon is called:
(A) Lateral inversion.
(B) Dispersion.
(C) Splitting.
(D) Refraction.

32.An object 5 cm high is placed in front of a plane mirror. What is the size of the image formed?
(A) 2.5 cm.
(B) 10 cm.
(C) 5 cm.
(D) None of these.

33.Which types of cells present on retina respond to the intensity of light?
(A) Cones.
(B) Rods.
(C) Both.
(D) None.

34.Which types of cells present on retina respond to the colours?
(A) Cones.
(B) Rods.
(C) Both.
(D) None.

35.A chicken's eye has very few ……….. shaped cells.
(A) Cone.
(B) Rod.
(C) Both.
(D) None.

36.The human eye forms the image of an object at its:
(A) Cornea.
(B) Iris.
(C) Pupil.
(D) Retina.

37.The part of eye, which is equivalent to the photographic film in a camera is:
(A) Cornea.
(B) Iris.
(C) Pupil.
(D) Retina.

38.The part, which controls the amount of light entering the eye, is
(A) Cornea.
(B) Iris.
(C) Pupil.
(D) Retina.

39.What kind of retinal cells are lacking in a person suffering from colour blindness?
(A) Cone.
(B) Rod.
(C) Both.
(D) None.

40.The image, which can be obtained on a screen is called:
(A) Real.
(B) Virtual.
(C) Upside.
(D) None.

41.Name the form of energy which enables us to see the objects?

42.What types of waves are light waves?

43.Define a ray of light.

44.Define a beam of light?

45.Give an example of best reflector of light.

46.What type of image is formed in a plane mirror?

47.What type of image is formed on a cinema screen?

48.If an object is placed at a distance of 10 cm in front of a plane mirror, how far would it be forms its image?

49.Give any three phenomena shown by light.

50.How can visually challenged persons read and write?

51.What do you mean by reflection of light?

52.How do we see objects?

53.If the incident ray strikes the mirror at 900, what will be the angle of reflection?

54.If angle of incident is 300 then what will be the value of angle of reflection?<

55.Name the instrument based on multiple reflection used to create new designs

56.Name one means of communication provided by light.

57.State the laws of reflection.

58.Write the names of important parts of eye.

59.A celestial body that revolves around a planet is known as

60.Shooting stars are actually not .

<2M>

61.Name two types of sources of light.

62.Define dispersion of light.

63.What is blind point?

<3M>

64.Why the world AMBULANCE is written as its mirror image in front of the hospital vans?

65.What do you mean by lateral inversion?

66.Draw a neat and labeled diagram of human eye.

67.Why is it important to take care of our eyes? Mention some activities that may cause damage to our eyes.

68.Write the functions of the following:
(a) Optic nerves.
(b) Retina.
(c) Cornea.

69.What do you mean by multiple reflection?

70.What is the angle of incidence of a ray if the reflected ray is it an angle of 90° to the incident ray

71.How many images of a candle will be formed if it is placed between two a parallel plane mirrors separated by 40 cm

72.How many images of a candle will be formed if it is placed between two a parallel plane mirrors separated by 40 cm

<5M>

73.Define regular and irregular reflection with the help of diagrams.

74.What are the two laws of reflection? Calculate angle of incidence and angle of reflection from the given diagram.

75.What are the characteristics of the image formed by a plane mirror? How is the position of image related to the position of the object?

 CBSE Class 8 Science - Light (4)

CBSE Class 8 Science - Light (4)

CBSE Class 8 Science - Light (4)

CBSE Class 8 Science - Light (4)

""CBSE-Class-8-Science-Light-Assignment-Set-D

Chapter 01 Crop Production and Management
CBSE Class 8 Science Crop Production And Management Assignment
Chapter 02 Microorganisms Friend or Foe
CBSE Class 8 Science Micro Organisms Friends and Foe Assignment
Chapter 03 Synthetic Fibres and Plastics
CBSE Class 8 Science Synthetic Fibers And Plastics Assignment
Chapter 04 Materials Metals and Non-Metals
CBSE Class 8 Science Materials Metals And Non Metals Assignment
Chapter 07 Conservation of Plants and Animals
CBSE Class 8 Science Conservation Of Plants And Animals Assignment
Chapter 08 Cell Structure and Functions
CBSE Class 8 Science Cell Structure and Functions Assignment
Chapter 09 Reproduction in Animals
CBSE Class 8 Science Reproduction in Animals Assignment
Chapter 10 Reaching the Age of Adolescence
CBSE Class 8 Science Reaching the age of Adolescence Assignment
Chapter 14 Chemical Effects of Electric Current
CBSE Class 8 Science Chemical Effects of Electric Current Assignment
Chapter 17 Stars and the Solar System
CBSE Class 8 Science Stars and the Solar System Assignment
Chapter 18 Pollution of Air and Water
CBSE Class 8 Science Pollution of Air and Water Assignment
Class 8 Science Revision Assignments
CBSE Class 8 Science Revision Assignment

More Study Material

CBSE Class 8 Science Chapter 16 Light Assignment

We hope you liked the above assignment for Chapter 16 Light which has been designed as per the latest syllabus for Class 8 Science released by CBSE. Students of Class 8 should download and practice the above Assignments for Class 8 Science regularly. We have provided all types of questions like MCQs, short answer questions, objective questions and long answer questions in the Class 8 Science practice sheet in Pdf. All questions have been designed for Science by looking into the pattern of problems asked in previous year examinations. 

Assignment for Science CBSE Class 8 Chapter 16 Light

Our team of expert teachers have referred to NCERT book for Class 8 Science to design the Science Class 8 Assignments. If you practice at least one test paper daily, you will get higher marks in Class 8 exams this year. Daily practice of Science course notes and related study material will help you to clear all your doubts and have stronger understanding of all concepts. You can download all Revision notes for Class 8 Science also from www.studiestoday.com absolutely free of cost.

Chapter 16 Light Assignment Science CBSE Class 8

All questions and their answers for the assignment given above for Class 8 Science have been developed as per the latest curriculum and books issued for the current academic year. The students of Class 8 can rest assured that the best teachers have designed the questions of Science so that you are able to revise the entire syllabus if you do the assignments. Lot of MCQ questions for Class 8 Science have also been given in the worksheets and assignments for regular use. All study material for Class 8 Science students have been given on studiestoday.

Chapter 16 Light Assignment CBSE Class 8 Science

Regular assignment practice helps to get a more comprehensive understanding of Chapter 16 Light concepts. Assignments play a crucial role in understanding Chapter 16 Light in CBSE Class 8. Students can download all the assignments of the same chapter in Class 8 Science in Pdf format. You can print them or read them online on your computer or mobile.

CBSE Science Class 8 Chapter 16 Light Assignment

CBSE Class 8 Science latest books have been used for coming up with the latest questions and solutions for the above assignment. If you have revised all concepts relating to Chapter 16 Light then you should attempt all questions given in the test sheets above. We have also provided lot of Worksheets for Class 8 Science which you can use to further make your self stronger in Science

Where can I download in PDF assignments for CBSE Class 8 Science Chapter 16 Light

You can download free Pdf assignments for CBSE Class 8 Science Chapter 16 Light from StudiesToday.com

The assignments for Chapter 16 Light Class 8 Science for have been made based on which syllabus

The Chapter 16 Light Class 8 Science Assignments have been designed based on latest CBSE syllabus for Class 8 Science issued for the current academic year

Can I download and print these printable assignments for Science Chapter 16 Light Class 8

Yes, These printable assignments for Chapter 16 Light Class 8 Science are free to download and print

How many topics are covered in Chapter 16 Light Science assignments for Class 8

All topics given in Chapter 16 Light Science Class 8 Book for the current academic year have been covered in the given assignment

Is there any charge for this assignment for Chapter 16 Light Science Class 8

No, all Printable Assignments for Chapter 16 Light Class 8 Science have been given for free and can be downloaded in Pdf format

How can I download the printable test assignments for Chapter 16 Light Science Class 8

Just click on the View or Download button below, then another window with the Pdf will be visible, just click on the Pdf icon to download the free assignments for Chapter 16 Light Class 8 Science

Are these assignments available for all chapters in Class 8 Science

Yes, apart from Science you can download free assignments for all subjects in Class 8

Can I download solved assignments for Chapter 16 Light CBSE Class 8 Science

Our team of expert teachers at studiestoday.com have provided all answers for the practice questions which have been given in Class 8 Science Chapter 16 Light assignments