# VBQs Light Reflection and Refraction Class 10 Science

VBQs Light Reflection and Refraction Class 10 Science with solutions has been provided below for standard students. We have provided chapter wise VBQ for Class 10 Science with solutions. The following Light Reflection and Refraction Class 10 Science value based questions with answers will come in your exams. Students should understand the concepts and learn the solved cased based VBQs provided below. This will help you to get better marks in class 10 examinations.

## Light Reflection and Refraction VBQs Class 10 Science

Question. The correct sequencing of angle of incidence, angle of emergence, angle of refraction and lateral displacement shown in the following diagram by digits 1, 2, 3 and 4 is:

(a) 2, 4, 1, 3
(b) 2, 1, 4, 3
(c) 1, 2, 4, 3
(d) 2, 1, 3, 4

B

Question. Which of the following ray diagrams is correct for the ray of light incident on a concave mirror as shown in figure?

(a) Fig. A
(b) Fig. B
(c) Fig. C
(d) Fig. D

D

Question. In your laboratory you trace the path of light rays through a glass slab for different values of angle of incidence (∠i) and in each case measure the values of the corresponding angle of refraction (∠r) and angle of emergence (∠e).
On the basis of your observation your correct conclusion is:
(a) ∠i is more than ∠r, but nearly equal to ∠e
(b) ∠i is less than ∠r, but nearly equal to ∠e
(c) ∠i is more than ∠e, but nearly equal to ∠r
(d) ∠i is less than ∠e, but nearly equal to ∠r

A

Question. The laws of reflection hold true for:
(a) plane mirrors only
(b) concave mirrors only
(c) convex mirrors only
(d) all reflecting surfaces

D

Question. Magnification produced by a rear-view mirror fitted in vehicles
(a) is less than one.
(b) is more than one.
(c) is equal to one.
(d) can be more than or less than one depending upon the position of the object in front of it.

A

Question. To determine the approximate focal length of the given convex lens by focussing a distant object (say, a sign board), you try to focus the image of the object on a screen. The image you obtain on the screen is always:
(a) erect and laterally inverted
(b) erect and diminished
(c) inverted and diminished
(d) virtual, inverted and diminished

C

Question. Which of the following can make a parallel beam of light when light from a point source is incident on it?
(a) Concave mirror as well as convex lens
(b) Convex mirror as well as concave lens
(c) Two plane mirrors placed at 90° to each other
(d) Concave mirror as well as concave lens

A

Question. Rays from sun converge at a point 15 cm in front of a concave mirror. Where should an object be placed so that size of its image is equal to the size of the object?
(a) 15 cm in front of the mirror
(b) 30 cm in front of the mirror
(c) Between 15 cm and 30 cm in front of the mirror
(d) More than 30 cm in front of the mirror

B

Question. 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
(a) away from the screen
(b) towards the screen
(c) to a position very far away from the screen
(d) either towards or away from the screen depending upon the position of the object

D

Question. When an object is kept within the focus of a concave mirror, an enlarged image is formed behind the mirror. This image is:
(a) real
(b) inverted
(c) virtual and inverted
(d) virtual and erect

D

Question. Suppose you have focussed on a screen the image of candle flame placed at the farthest end of the laboratory table using a convex lens. If your teacher suggests you to focus the parallel rays of sun, reaching your laboratory table, on the same screen, what you are expected to do is to move the:
(a) lens slightly towards the screen
(b) lens slightly away from the screen
(c) lens slightly towards the sun
(d) lens and screen both towards the sun

A

Question. 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
(a) Convex mirror of focal length 12 cm
(b) Convex lens of focal length 24 cm
(c) Concave mirror of focal length 24 cm
(d) Convex lens of focal length 12 cm

C

Question. Select from the following the best experimental set-up for tracing the path of a ray of light passing through a rectangular glass slab:

(a) P
(b) Q
(c) R
(d) S

D

Question. To determine the approximate value of the focal length of a given concave mirror, you focus the image of a distant object formed by the mirror on a screen. The image obtained on the screen, as compared to the object is always:
(a) Laterally inverted and diminished
(b) Inverted and diminished
(c) Erect and diminished
(d) Erect and highly diminished

B

Question. 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:
(a) away from the screen
(b) towards the screen
(c) to a position very far away from the screen
(d) either towards or away from the screen depending upon the position of the object.

D

Question. A student obtained a sharp image of a candle flame placed at the distant end of the laboratory table on a screen using a concave mirror to determine its focal length. The teacher suggested him to focus a distant building about 1 km far from the laboratory, for getting more correct value of the focal length.
In order to focus the distant building on the same screen the student should slightly move the:
(a) mirror away from the screen
(b) screen away from the mirror
(c) screen towards the mirror
(d) screen towards the building

C

Question. A light ray enters from medium A to medium B as shown in the figure. The refractive index of medium B relative to A will be

(a) Greater than unity
(b) Less than unity
(c) Equal to unity
(d) Zero

A

Question. A student determines the focal length of a device ‘X’ by focussing the image of a distant object on a screen placed 20 cm from the device on the same side as the object. The device ‘X’ is
(a) Concave lens of focal length 10 cm
(b) Convex lens of focal length 20 cm
(c) Concave mirror of focal length 10 cm
(d) Concave mirror of focal length 20 cm

D

Question. A spherical mirror and a thin spherical lens have each a focal length of -15 cm. The mirror and the lens are likely to be
(a) both concave.
(b) both convex.
(c) the mirror is concave and the lens is convex.
(d) the mirror is convex, but the lens is concave.

A

Question. A teacher sets up the stand carrying a convex lens of focal length 15 cm at 42.7 cm mark on the optical bench. He asks four students A, B, C and D to suggest the position of screen on the optical bench so that a distinct image of a distant tree is obtained almost immediately on it. The positions suggested by the students were as :
(i) 12.7 cm (ii) 29.7 cm
(iii) 57.7 cm (iv) 72.7 cm
The correct position of the screen was suggested by
(a) (i)
(b) (ii)
(c) (iii)
(d) (iv)

C

Question. A student very cautiously traces the path of a ray through a glass slab for different values of the angle of incidence (∠i). He then measures the corresponding values of the angle of refraction (∠r) and the angle of emergence (∠e) for every value of the angle of incidence. On analyzing these measurements of angles, his conclusion would be
(a) ∠i > ∠r > ∠e
(b) ∠i = ∠e > ∠r
(c) ∠i < ∠r < ∠e
(d) ∠i = ∠e < ∠r

B

Question. Which of the following lenses would you prefer to use while reading small letters found in a dictionary?
(a) A convex lens of focal length 50 cm
(b) A concave lens of focal length 50 cm
(c) A convex lens of focal length 5 cm
(d) A concave lens of focal length 5 cm

C

Question. In torches, search lights and headlights of vehicles, the bulb is placed
(a) between the pole and the focus of the reflector.
(b) very near to the focus of the reflector.
(c) between the focus and centre of curvature of the reflector.
(d) at the centre of curvature of the reflector.

B

Question. Figure shows a ray of light as it travels from medium A to medium B. Refractive index of the medium B relative to medium A is

(a) √3/√2
(b) √2/√3
(c) 1/√2
(d) √2

A

Question. Consider the following properties of virtual images:
(i) cannot be projected on the screen
(ii) are formed by both concave and convex lens
(iii) are always erect
(iv) are always inverted
The correct properties are:
(a) (i) and (iv)
(b) (i) and (ii)
(c) (i), (ii) and (iii)
(d) (i), (ii) and (iv)

C

Question. Which of the following statements is true?
(a) A convex lens has 4 dioptre power having a focal length 0.25 m
(b) A convex lens has – 4 dioptre power having a focal length 0.25 m
(c) A concave lens has 4 dioptre power having a focal length 0.25 m
(d) A concave lens has – 4 dioptre power having a focal length 0.25 m

A

Question. A real image is formed by the light rays after reflection or refraction when they:
(i) actually meet or intersect with each other.
(ii) actually converge at a point.
(iii) appear to meet when they are produced in the backward direction.
(iv) appear to diverge from a point.
Which of the above statements are correct?
(a) (i) and (iv)
(b) (ii) and (iv)
(c) (i) and (ii)
(d) (ii) and (iii)

C

Question. Study the given ray diagrams and select the correct statement from the following:

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

D

Assertion And Reason Based MCQs :

Directions : In the following questions, A statement of Assertion (a) is followed by a statement of Reason (R). Mark the correct choice as.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is NOT the correct explanation of A.
(c) A is true but R is false.
(d) A is false and R is True.

Question. Assertion (A): The image formed by a concave mirror is certainly real if the object is virtual.
Reason (R): The image formed by a concave mirror is certainly virtual if the object is real.

C

Question. Assertion: Light travels faster in glass than in air.
Reason: Glass is denser than air.

D

Question. Assertion (A): If the rays are diverging after emerging from a lens; the lens must be concave.
Reason (R): The convex lens can give diverging rays.

D

Question. Assertion (A): The refractive index of diamond is √6 and refractive index of a liquid is √3 . If the light travels from diamond to the liquid, it will be initially reflected when the angle of incidence is 30°.
Reason (R): µ = 1/sin C, where m is the refractive index of diamond with respect to liquid.

A

Question. Assertion (A): Plane mirror may form real image.
Reason (R): Plane mirror forms virtual image, if object is real.

B

Question Assertion (A): The focal length of the convex mirror will increase, if the mirror is placed in water.
Reason (R): The focal length of a convex mirror of radius R is equal to, f =R/2.

D

Question. Assertion (A): Refractive index of glass with respect to air is different for red light and violet light.
Reason (R): Refractive index of a pair of media depends on the wavelength of light used.

A

Question. Assertion (A): An object is placed at a distance of f from a convex mirror of focal length f, its image will form at infinity.
Reason (R): The distance of image in convex mirror can never be infinity.

D

Case Based Questions :

I. Following figure illustrates the ray diagram for the formation of image by a concave mirror. The position of the object is beyond the centre of curvature of the concave mirror. On the basis of given diagram answer any four questions from

Question. If the size of the object in the given figure is 5 cm and the magnification produced is –0.5. The size of the image is (in cm) ___________
(a) –2.5
(b) –0.1
(c) 2.5
(d) 0.1

A

Question. A negative sign in the magnification value indicate that the image is ____________
(a) Real and inverted
(b) Real and erect
(c) Virtual and erect
(d) Virtual and inverted

A

Question. An image formed by concave mirror is virtual, when the object is placed:
(a) at infinity
(b) at C
(c) Between C and F
(d) Between P and F

D

Question. If the focal length of the concave mirror is 10 cm, the image formed will be at a distance ___________.
(a) Between 10cm and 15cm
(b) Between 10cm and 20cm
(c) Beyond 20cm
(d) At 20 cm

B

Question. In case of concave mirror, the image distance is _________ when image is formed in front of the mirror and _________________ when the image is formed behind the mirror.
(a) positive, negative
(b) negative, negative
(c) negative, positive
(d) positive , positive

C

II. Read the following passage and answer any four questions from A student wants to project the image of a candle flame on the walls of the school laboratory by using a mirror.

Question. Which type of mirror should he use and why ?
(a) Convex mirror, it forms virtual image
(b) Concave mirror, it forms virtual image
(c) Concave mirror, it forms real image
(d) Convex mirror, it forms real image

C

Question. If the image formed by this mirror is inverted and real, the magnification will be:
(a) Positive
(b) Negative
(c) Either of them
(d) None of the above

B

Question. A virtual image formed by concave mirror is:
(a) erect and enlarged
(b) erect and diminished
(c) inverted and diminished
(d) inverted and enlarged

A

Question. At what distance, in terms of focal length ‘f’ of the mirror, should he place the candle flame to get the magnified image on the wall ?
(a) At F
(b) Between F and C
(c) At C
(d) At infinity

B

Question. To get the diminished image of the candle flame, the object must be placed at:
(a) infinity
(b) at C
(c) between F and C
(d) At F

A

III. Read the following passage and answer any four questions from A student wants to project the image of a candle flame on a screen 60 cm in front of a mirror by keeping the flame at a distance of 15 cm from its pole.

Question. When object distance is less than focal length the image is _______ and when object distance is more than focal length the image is ______.
(a) real in both case
(b) virtual in both case
(c) real, virtual
(d) virtual, real

D

Question. What is the distance between the object and its image ?
(a) 45 cm
(b) 35 cm
(c) 75 cm
(d) 0 cm

A

Question. Suggest the type of mirror he should use:
(a) convex mirror
(b) plane mirror
(c) concave mirror
(d) none of the above

C

Question. Find the linear magnification of the image produced.
(a) – 4
(b) + 4
(c) – 900
(d) + 900

A

Question. The image formed in the above case is:
(a) virtual, inverted and magnified.
(b) real, erect and magnified
(c) real , inverted and magnified
(d) real, erect and diminished

C

IV. Read the following passage and answer the following questions from A student focuses the image of a candle flame, placed at about 2 m from a convex lens of focal length 10 cm, on a screen. After that he moves gradually the flame towards the lens and each time focuses its image on the screen.

Question. What difference is seen in the intensity (brightness) of the image of the flame on the screen ?
(a) intensity of image increases
(b) intensity of image remains same
(c) intensity of image reduces
(d) the image disappears

A

Question. What is seen on the screen when the flame is very close (at about 5 cm) to the lens ?
(a) a bright image
(b) a magnified image
(c) diminished image
(d) no image

D

Question. In which direction does he move the lens to focus the flame on the screen ?
(a) away from screen
(b) towards the screen
(c) should not move the screen
(d) toward the candle

D

Question. What happens to the size of the image of the flame formed on the screen?
(a) size of image will decrease
(b) size of image will increase
(c) remains unchanged
(d) size will become too small

B

V. Read the passage and note the following observations. Answer any four questions from A student focussed the image of a candle flame on a white screen by placing the flame at various distances from a convex lens. He noted his observations as:

Question. From the above table, find the focal length of lens without using lens formula:
(a) 15cm
(b) 30cm
(c) 40cm
(d) 60cm

A

Question. What is the change in image observed as the object is moved from infinity towards the concave lens?
(a) Size of image decreases
(b) Size of image becomes highly diminished
(c) Size of the image remains unchanged
(d) Size of the image increases slightly

D

Question. Which of the following statement is false for the formation of images by convex lens?
(a) It forms real,inverted and diminished image.
(b) It forms virtual erect and enlarged image.
(c) It forms virtual, erect, and diminished image.
(d) It forms real,inverted and enlarged image.

C

Question. Which set of observations is incorrect?
(a) (a)
(b) (c)
(c) (e)
(d) (d)

C

Question. In which case, the size of the object and image will be same:
(a) In (d) case
(b) In (b) case
(c) In (c) case
(d) In (a) case

C

VI. Study the given diagram and answer any four questions from A very thin narrow beam of white light is made incident on three glass objects shown below.
Study the nature and behaviour of the emergent beam in all the three cases.

Question. The light changes its path as its medium changes.
Which of the following is an incorrect statement ?
(a) Speed of light is different in different media.
(b) Light changes its path because light only travels in straight line.
(c) Speed of light is dependent on medium through which it is passing.
(d) The light chooses the path with minimum time, as it changes its medium.

B

Question. What is the unit of refractive index?
(a) Pascal
(b) Joule
(c) No unit
(d) μ m

C

Question. When light enters from air to glass, the angles of incidence and refraction in air and glass are 45° and 30°, respectively. Find the refractive index of glass.
(Given that sin 45°=1/√2 ; sin 30°= 1/2)
(a) √2
(b) 2 √2
(c) 1/(√2)
(d) 1

A

Question. Light travel fastest in:
(a) Air
(b) Vacuum
(c) Glass
(d) diamond