SSC Worksheet for chapter-3 Wonder of Light - Part I class 10

Worksheet For class 10

Find SSC Worksheet for chapter-3 Wonder of Light - Part I class 10

CLASS-10

BOARD: SSC

Physics Worksheet-3

TOPIC: Wonder of Light - Part I

For other SSC Worksheet for class 10 Physics check out main page of Physics Wallah. 

1. For a normal human eye, distance of distinct vision is about

(a) 15 cm

(b) 25 cm

(c) 35 cm

(d) 5 cm

2. Power of a convex lens of focal length 40 cm is

(a) 40 D

(b) 0.4 D

(c) 2.5 D

(d) 0.25 D

3. Focal length of a convex lens of power – 2D is.

(a) –2 cm

(b) –0.5 m

(c) –2 m

(d) –5 m

4. Image formed by convex mirror is always

(a) real and magnified

(b) virtual and diminished

(c) real and diminished

(d) virtual and magnifies

5. When an object is placed at centre of curvature of a concave mirror, image formed is

(a) real and magnified

(b) virtual and magnified

(c) real and of same size as object

(d) virtual & of some size of object

6. When an object is placed between focus and centre of curvature of a concave mirror, image formed is

(a) real and magnified

(b) real and diminished

(c) virtual and magnified

(d) virtual and diminished

7. When object is placed beyond 2f₁ for convex lens image formed is

(a) real and diminished

(b) real and magnified

(c) virtual and diminished

(d) virtual and magnified

8. When object is placed between f₁ & 2f₁ in front of a convex lens, image formed is

(a) real and magnified

(b) virtual and diminished

(c) virtual and magnified

(d) real and diminished

9. When an object is placed between focus f₁ and optical centre O of a convex lens, image formed is

(a) real and diminished

(b) virtual and diminished

(c) real and magnified

(d) virtual and magnified

Fill in​ the blanks

10. ________ mirror always forms a virtual image of same size as that of object.

11. _______ mirror forms a real image or virtual image depending on position of object.

12. _______ mirror can form a virtual image which is larger in size than object

13. _______ mirror always forms a virtual diminished image

14. _________ Lens can form a real or virtual image depending on position of object

15. Type of lens used to correct myopia is ________& type of lens used to correct hypermetropia is ______

16. Define the following terms related to concave mirror.

(a) Pole

(b) Principal axis

(c) Radius of curvature

(d) focal length

17. Draw ray diagrams for following positions of object for concave mirror

(a) Infinity

(b) Between Infinity & centre & curvature

(c) At centre of curvature

(d) between focus and centre of curvature

(f) At focus

(e) between pole & focus

18. Draw ray diagram for following positions of object for convex lens

(a) infinity

(b) Beyond 2f₁

(c) At 2f₁

(d) between f₁ & 2f₁

(e) At focus f₁

(f) Between f₁ & optical centre O

19. Write the rules used for drawing ray diagrams for formation of an image by concave mirror.

20. State positions of source of light with respect to concave mirror in

(a) Torches and headlights

(b) floodlight s

(c) Reflecting mirrors for projector lamps

(d) Shaving mirror, dentist’s mirror

21. Describe following applications of convex lens

(a) Simple microscope

(b) Compound microscope

(c) Telescope

(d) Spectacles

22. With neat diagram describe the components of human eye

23. What is power of accommodation of human eye?

24. With help of neat diagram, describe the use of concave lens to rectify myopia.

25. With the help of neat diagram, describe use of convex lens to rectify hypermetropia.

26. At what distance from a concave mirror of 2.5 m focal length should a boy stand so that his image is half his height

27. An object of height 2cm is placed 10cm in front of a concave mirror of focal length 3cm. Find size of image

28. When an object is kept at 6cm in front of a concave mirror, its image is obtained at 24cm behind mirror. Find Radius of curvature of mirror

29. When a pin of height 3cm is fixed at 10cm from a convex lens, height of virtual image formed is 12cm. Find focal length of lens

30. An object of height 2cm is kept at 30cm from a convex lens. Its real image is formed at 60cm from the lens. Find the power of the lens

31. What is near point of a human eye?

32. Draw a ray diagram to show the position of the image formed by a convex lens for an object placed between the principal focus and optical centre.

33. What are the functions of the pupil of a human eye?

34. A convex mirror used on automobile has a radius of curvature of 3m. If a truck is located 5m away from this mirror, find the position, nature and magnification of the image.

35. Explain the new Cartesian sign convection for spherical mirrors.

Solutions: to worksheet-3 Topic-Wonder of Light - Part I 

Objective Problems:

1. (b)

2. (c)

3. (b)

4. (b)

5. (c)

6. (a)

7. (a)

8. (a)

9. (d)

10. Plane

11. Concave

12. Concave

13. Convex

14. Convex

15. concave, convex

26. 7.5 m

27.

28. 16 cm

29. 13.33 cm

30. 5D

WONDER OF LIGHT – PART I ( 10^th class ) Solution

16.

(a) The pole(denoted by P in the figure) is defined as the geometric center of the curved mirror

(b) The principal axisof a curved mirror is defined as the imaginary line passing through its pole P and center of curvature C

(c) The radius of curvature(denoted by CP in the figure) of a curved mirror is defined as the radius of the hollow glass sphere of which the spherical mirror was (previously) a part.

(d) The focal length(denoted by FP in the figure) is the distance between the pole P and the principal focus F of a curved mirror.

17.

Ray diagram for positions of object for concave mirror

(a) Infinity

(b) Between infinite &centre of curvature

(c) At centre of curvature

(d) Between focus and centre of curvature

(e) At focus

(f)Between plane and focus

18.

(a) infinity

(b) beyond 2f

(c) At 2f

(d) between f and 2f

(e) At focus f

(f) Between f and optical centre O

19. Rules

(a) Any incident ray travelling parallel to the principal axis on the way to the mirror will pass through the focal point upon reflection.

(b) Any incident ray passing through the focal point on the way to the mirror will travel parallel tothe principal axis upon reflection.

(c) A ray passing through or directed towards the centre of curvature, after reflection from the spherical mirror, retraces its path

20.

(a) Torches and head light: The source of light is placed at focus to obtain a parallel beam of light.

(b) Flood lights: The source of light is placed at just beyond the centre of curvature so as to get intense beam of light.

(c) Reflecting mirrors for projector lights: source of light is placed at the centre of curvature so as to obtain an image of the same size.

(d) Shaving mirror, dentist mirror: It produces an erect virtual and highly magnified image of an object placed between its pole and focus.

21.

(a) Simple microscope A single convex lens of small focal length can be used as a simple microscope. A magnification of about 20 times is obtained by simple microscope. Watch repairer , jewellers, etc use it.

(b) Compound microscope:

The combinations of two convex lenses having short focal length are used in compound microscope. It is used to observe bacteria, viruses, cells, micro-organisms, etc.

(c) Telescope: A combination of two convex lenses is used in telescopes. An astronomical telescope is

used to get detailed view of astronomical bodies like planets, stars, etc. Terrestrial telescope is used to study terrestrial objects.

(d) Spectacle

Convex lens is used in spectacles to correct defect like hypermetropia.

22.

Cornea: The cornea is the transparent tissue at the front of the eyes through which light coming from an object enters the eye. It also helps in focusing the light on the retina.

Aqueous Humour: It is a clear transparent fluid that fills the space between the cornea and the eye lens.

It also supplies nutrients and oxygen to these parts.

Iris: The iris is a ring of muscles in the central part of the eye, that is helpful in regulating the amount of light entering the eye by controlling the size of the pupil.

Pupil: This is an opening in the center of the iris through which light passes and falls on the eye lens. Its size is controlled by the iris.

Eye Lens: The lens of the eye is situated directly behind the pupil. It helps in focusing the light on the retina. The eye lens is capable of changing its shape so as to enable us to see objects near and far.

Ciliary Muscles: This is a ring-shaped tissue that holds and controls the movement of the eye lens, and therefore, helps in controlling the shape of the lens.

Vitreous Humor: It acts as filler and covers the space between the eye lens and retina. It also provides protection to the lens. It makes up for about two-thirds of the total volume of the eye, and is composed mainly of water.

Retina: It is a membrane responsible for converting the light falling on it into electrical impulses that can be sent to the brain. The retina contains light-sensitive photoreceptor cells called rods and cones. The rods help in black and white vision and for seeing in dim light, while the cones help in daytime and color vision.

Optic Nerve: It is a bundle of nerve fibres that serve as a cable that connects the eye to the brain. This optic nerve helps in transmitting signals from the retina to the visual center of the brain.

23. The process by which the ciliary muscles change the focal length of an eye lens to focus distant or near objects clearly on the retina is called the accommodation of the eye. To focus on distant objects the

ciliary muscles relax making the eye lens thin. As a result the focal length of the eye lens increases and

we see the distant objects. But to focus on nearby objects the ciliary muscles contract making the eye lens thick. As a result the focal length of the eye lens decreases and we see the nearby objects.

In short it is the adjustment of the focal length of the eye lens which enables us to focus on objects situated at different distances.

24.

A myopic eye forms the image of a far off object in front of the retina because of the increase in converging power of the eye lens. Therefore myopia can be rectified by using a suitable divergent or concave lens.

25.

A long sighted eye forms image of a nearby object behind the retina. Thus, long sightedness is due to the decreased converging power of the lens. Therefore hypermetropia can be rectified by making the eye lens more convergent. This is done by placing convex lens of suitable focal length before the eye lens as shown in figure.