Class 10 Science · Chapter 9

Light - Reflection and Refraction

409 Class 10 Science questions on Light - Reflection and Refraction from the NCERT textbook, NCERT Exemplar and CBSE board papers 2017–2026, each with its answer and a step-by-step solution.

CBSE Class 10 Science previous year papers, with answers →

Questions · page 20 of 21

1. Q381 CBSE 2017
   The ​focal length of ​the concave mirror ​in the following ​experimental ​set ​up is

   1. (a)$12.4$ cm
   2. (b)$6.2$ cm
   3. (c)$6.0$ cm
   4. (d)$3.0$ cm
   Show answer

   (b) $6.2$ cm

   Step-by-step solution →
2. Q382 CBSE 2017
   A student has focussed ​on the screen a ​distant building ​using a convex lens. ​If he has selected a ​blue coloured building ​as object, select from the following ​options the one which gives the correct ​characteristics of the image formed on the screen.

   1. (a)Virtual, erect, diminished and green shade
   2. (b)Real, inverted, diminished and in violet shade
   3. (c)Real, inverted, diminished and in blue shade
   4. (d)Virtual, inverted, diminished and in blue shade
   Show answer

   (c) Real, inverted, diminished and in blue shade

   Step-by-step solution →
3. Q383 CBSE 2017
   Select from the following ​the best experimental ​set-up for ​tracing ​the path of ​a ray ​of light passing through ​a glass slab.

   1. (a)A
   2. (b)B
   3. (c)C
   4. (d)D
   Show answer

   (c) C

   Step-by-step solution →
4. Q384 CBSE 2017
   Study the following four experimental ​setups by four ​students A, B, C and ​D ​showing the incident ray to trace the ​path of a ray of light through ​a glass slab. Which of these will get the best result ?

   1. (a)(A)
   2. (b)(B)
   3. (c)(C)
   4. (d)(D)
   Show answer

   (d) (D)

   Step-by-step solution →
5. Q385 CBSE 2017
   Your ​school ​laboratory has one large window. To find the focal length of a ​concave mirror using one of the walls as screen, ​the experiment ​may ​be ​performed :

   1. (a)on the same wall as the window.
   2. (b)on the wall adjacent to the window.
   3. (c)on the wall opposite to the window.
   4. (d)only on the table as per laboratory arrangement.
   Show answer

   (a) on the same wall as the window.

   Step-by-step solution →
6. Q386 CBSE 2017
   Select from the following diagram the ​incident rays whose ​paths ​after refraction have been ​correctly shown and can be used for ​locating the ​position ​of image formed by a convex lens.

   1. (a)only 1 and 4
   2. (b)only 3 and 4
   3. (c)1, 3 and 4
   4. (d)1, 3, 4 and 5
   Show answer

   (c) 1, 3 and 4

   Step-by-step solution →
7. Q387 CBSE 2017
   A student determined the ​focal length ​of ​a device ‘X’ by focusing ​a bright distant object on the screen as shown ​in the ​diagram : According ​to the diagram, select ​the correct statement from the following :

   1. (a)Device ‘X’ is a concave mirror and distance ‘d’ is its focal length.
   2. (b)Device ‘X’ is a concave mirror and distance ‘d’ is its radius of curvature.
   3. (c)Device ‘X’ is a convex lens and distance ‘d’ is its focal length.
   4. (d)Device ‘X’ is a convex lens and distance ‘d’ is its radius of curvature.
   Show answer

   (c) Device ‘X’ is a convex lens and distance ‘d’ is its focal length.

   Step-by-step solution →
8. Q388 CBSE 2017
   Three ​students A, B and C focussed a distant ​building on a screen with the help of a concave ​mirror. To determine focal ​length of the concave mirror they measured the distances as given below : Student A : From mirror to the screen Student B : From ​building to ​the screen Student C : From building to the mirror Who measured ​the focal length correctly :

   1. (a)Only A
   2. (b)Only B
   3. (c)A and B
   4. (d)B and C
   Show answer

   (a) Only A

   Step-by-step solution →
9. Q389 CBSE 2017
   An ​optical device has been given to a student and he ​determines its focal length by focusing the image of ​the sun on a ​screen placed ​24 cm from the device on ​the same side as the sun. Select the correct ​statement about the ​device.

   1. (a)Convex mirror of focal length 12 cm
   2. (b)Convex lens of focal length 24 cm
   3. (c)Concave mirror of focal length 24 cm
   4. (d)Convex lens of focal length 12 cm
   Show answer

   (c) Concave mirror of focal length 24 cm

   Step-by-step solution →
10. Q390 CBSE 2017
    Study ​the given ​ray diagrams and ​select ​the correct ​statement ​from the ​following :

    1. (a)Device X is a concave mirror and device Y is a convex lens, whose focal lengths are 20 cm and 25 cm respectively.
    2. (b)Device X is a convex lens and device Y is a concave mirror, whose focal lengths are 10 cm and 25 cm respectively.
    3. (c)Device X is a concave lens and device Y is a convex mirror, whose focal lengths are 20 cm and 25 cm respectively.
    4. (d)Device X is a convex lens and device Y is a concave mirror, whose focal lengths are 20 cm and 25 cm respectively.
    Show answer

    (d) Device X is a convex lens and device Y is a concave mirror, whose focal lengths are 20 cm and 25 cm respectively.

    Step-by-step solution →
11. Q391 CBSE 2017
    A student has to determine the focal length of a given

    1. (i)concave mirror ;
    2. (ii)​convex lens by ​focusing the image of a distant object ​on a screen. He would observe ​that ​the screen ​is placed ​on the same side ​as the object :

    1. (a)in both cases
    2. (b)in neither of the two cases
    3. (c)in case (i) and not in case (ii)
    4. (d)in case (ii) and not in case (i)
    Show answer

    (c) in case (i) and not in case (ii)

    Step-by-step solution →
12. Q392 CBSE 2017
    If ​you focus a ​distant ​object of the shape shown in ​the figure ​using ​a concave mirror, ​the image obtained ​must be of the shape

    1. (a)Pole along the right edge of the crossed rectangle, rising above it; the half-round tab at the top of the pole bulges to the right
    2. (b)Pole along the left edge of the crossed rectangle, rising above it; the half-round tab at the top of the pole bulges to the left
    3. (c)Pole along the left edge of the crossed rectangle, hanging below it; the half-round tab at the bottom of the pole bulges to the left
    4. (d)Pole along the right edge of the crossed rectangle, hanging below it; the half-round tab at the bottom of the pole bulges to the right
    Show answer

    (c) Pole along the left edge of the crossed rectangle, hanging below it; the half-round tab at the bottom of the pole bulges to the left

    Step-by-step solution →
13. Q393 CBSE 2017
    A ​student carries out the experiment of tracing the path of a ray of light through a ​rectangular glass slab for two different values of angle of ​incidence $\angle i=30^{\circ }$ ​and $\angle i=45^{\circ }$. In ​the two cases the student is likely to ​observe the set of values ​of angle of refraction and ​angle of emergence as :

    1. (a)$\angle r=30^{\circ }$, $\angle e=20^{\circ }$ and $\angle r=45^{\circ }$, $\angle e=28^{\circ }$
    2. (b)$\angle r=30^{\circ }$, $\angle e=30^{\circ }$ and $\angle r=45^{\circ }$, $\angle e=45^{\circ }$
    3. (c)$\angle r=20^{\circ }$, $\angle e=30^{\circ }$ and $\angle r=28^{\circ }$, $\angle e=45^{\circ }$
    4. (d)$\angle r=20^{\circ }$, $\angle e=20^{\circ }$ and $\angle r=28^{\circ }$, $\angle e=28^{\circ }$
    Show answer

    (c) $\angle r=20^{\circ }$, $\angle e=30^{\circ }$ and $\angle r=28^{\circ }$, $\angle e=45^{\circ }$

    Step-by-step solution →
14. Q394 CBSE 2017
    If ​you focus the ​image of a ​distant object, whose ​shape is given below, on ​a screen ​using a convex lens, the shape of ​the image of this object on the screen would be :

    1. (a)Upward arrow top left, one dot top right, bottom left empty, two dots bottom right
    2. (b)Top left empty, two dots top right, downward arrow bottom left, one dot bottom right
    3. (c)Two dots top left, top right empty, one dot bottom left, downward arrow bottom right
    4. (d)One dot top left, upward arrow top right, two dots bottom left, bottom right empty
    Show answer

    (c) Two dots top left, top right empty, one dot bottom left, downward arrow bottom right

    Step-by-step solution →
15. Q395 CBSE 2017
    Select from the following ​the ​best experimental set-up ​for tracing ​the path of ​a ray ​of ​light through a glass slab :

    1. (a)I
    2. (b)II
    3. (c)III
    4. (d)IV
    Show answer

    (b) II

    Step-by-step solution →
16. Q396 CBSE 2017
    A student ​obtains a blurred image of a distant object on a screen ​using ​a convex ​lens. To ​obtain a ​distinct ​image on the screen ​he should move the lens

    1. (a)away from the screen
    2. (b)towards the screen
    3. (c)to a position very far away from the screen
    4. (d)either towards or away from the screen depending upon the position of the object
    Show answer

    (d) either towards or away from the screen depending upon the position of the object

    Step-by-step solution →
17. Q397 CBSE 2017
    A student has to determine the focal length ​of ​a ​given convex ​lens by focusing a ​distant object on a screen, ​for this experiment ​he should ​have

    1. (a)convex lens and screen
    2. (b)convex lens, lens holder and screen
    3. (c)lens holder and scale
    4. (d)convex lens, screen, holders for both and scale
    Show answer

    (d) convex lens, screen, holders for both and scale

    Step-by-step solution →
18. Q398 CBSE 2017
    In which ​of the following diagrams ​has the protractor (D) been ​correctly placed ​to measure the angle ​of incidence ​and the angle of emergence ?

    1. (a)I, III
    2. (b)I, IV
    3. (c)II, III
    4. (d)II, IV
    Show answer

    (a) I, III

    Step-by-step solution →
19. Q399 CBSE 2017
    A student very cautiously traces the path of a ray through ​a glass ​slab for different values of the angle of incidence ​($\angle i$). He then measures the ​corresponding values of the angle of refraction ($\angle r$) and the ​angle of ​emergence ($\angle e$) ​for every value of the angle of incidence. On analysing these measurements of angles, his conclusion would ​be

    1. (a)$\angle i>\angle r>\angle e$
    2. (b)$\angle i=\angle e>\angle r$
    3. (c)$\angle i<\angle r<\angle e$
    4. (d)$\angle i=\angle e<\angle r$
    Show answer

    (b) $\angle i=\angle e>\angle r$

    Step-by-step solution →
20. Q400 CBSE 2017
    A student has traced ​the path of light ​rays ​for different angles of ​incidence. On the ​basis ​of observation he must ​conclude that

    1. (a)angle of incidence is smaller than the angle of refraction but is equal to the angle of emergence.
    2. (b)angle of incidence is greater than the angle of refraction but is equal to the angle of emergence.
    3. (c)angle of incidence is greater than the angle of emergence but equal to the angle of refraction.
    4. (d)angle of incidence is smaller than the angle of emergence but equal to the angle of refraction.
    Show answer

    (b) angle of incidence is greater than the angle of refraction but is equal to the angle of emergence.

    Step-by-step solution →