31 + Mcqs in Ray optics Page 1 McqOptions

1.	Assertion : The focal length of lens does not change when red light is replaced by blue light. Reason : The focal length of lens does not depends on colour of light used.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» E.

Discussion

2.	Assertion : The images formed by total internal reflections are much brighter than those formed by mirrors or lenses. Reason : There is no loss of intensity in total internal reflection.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

3.	Assertion : Within a glass slab, a double convex air bubble is formed. This air bubble behaves like a converging lens. Reason : Refractive index of air is more than the refractive index of glass.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» E.

Discussion

4.	Assertion : A piece of red glass is heated till it glows in dark. The colour of glowing glass would be orange. Reason : Red and orange is complementary colours.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» E.

Discussion

5.	Assertion : We cannot produce a real image by plane or convex mirrors under any circumstances. Reason : The focal length of a convex mirror is always taken as positive.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If assertion is false but reason is true.
Answer» E.

Discussion

6.	Assertion : Critical angle of light passing from glass to air is minimum for violet colour. Reason : The wavelength of blue light is greater than the light of other colours.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» D. If the assertion and reason both are false.

Discussion

7.	Assertion : Just before setting, the sun may appear to be elliptical. This happens due to refraction. Reason : Refraction of light ray through the atmosphere may cause different magnification in mutually perpendicular directions.
A.	Assertion : Just before setting, the sun may appear to be elliptical. This happens due to refraction. Reason : Refraction of light ray through the atmosphere may cause different magnification in mutually perpendicular directions.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

8.	Assertion : The size of the mirror affect the nature of the image. Reason : Small mirrors always forms a virtual image.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» E.

Discussion

9.	Assertion : The mirrors used in search lights are parabolic and not concave spherical. Reason : In a concave spherical mirror the image formed is always virtual.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» D. If the assertion and reason both are false.

Discussion

10.	Assertion : When an object is placed between two plane parallel mirrors, then all the images found are of equal intensity. Reason : In case of plane parallel mirrors, only two images are possible.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false
D.	If the assertion and reason both are false.
Answer» E.

Discussion

11.	Assertion : The illumination of earth's surface from sun is more at noon than in the morning. Reason : Luminance of a surface refers to brightness of the surface.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» C. If assertion is true but reason is false.

Discussion

12.	Assertion : The polar caps of earth are cold in comparison to equatorial plane. Reason : The radiation absorbed by polar caps is less than the radiation absorbed by equatorial plane.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» D. If the assertion and reason both are false.

Discussion

13.	Assertion : The fluorescent tube is considered better than an electric bulb. Reason : Efficiency of fluorescent tube is more than the efficiency of electric bulb.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

14.	Assertion : If a plane glass slab is placed on the letters of different colours all the letters appear to be raised up to the same height. Reason : Different colours have different wavelengths.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If assertion is false but reason is true.
Answer» E.

Discussion

15.	Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light. [AIIMS 1997]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

16.	Assertion : Different colours travel with different speed in vacuum. Reason : Wavelength of light depends on refractive index of medium. [AIIMS 1998]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If assertion is false but reason is true.
Answer» E.

Discussion

17.	Assertion : The setting sun appears to be red. Reason : Scattering of light is directly proportional to the wavelength. [AIIMS 2000]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» D. If the assertion and reason both are false.

Discussion

18.	Assertion : The refractive index of diamond is  6√  and that of liquid is  3√ . If the light travels from diamond to the liquid, it will totally reflected when the angle of incidence is 30o. Reason :  μ=1sinC,  where m is the refractive index of diamond with respect to liquid. [AIIMS 2000]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If assertion is false but reason is true.
Answer» E.

Discussion

19.	Assertion : Blue colour of sky appears due to scattering of blue colour. Reason : Blue colour has shortest wave length in visible spectrum. [AIIMS 2001]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

20.	Assertion : In a movie, ordinarily 24 frames are projected per second from one end to the other of the complete film. Reason : The image formed on retina of eye is sustained upto 1/10 second after the removal of stimulus. [AIIMS 2001]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» D. If the assertion and reason both are false.

Discussion

21.	Assertion : The air bubble shines in water. Reason : Air bubble in water shines due to refraction of light [AIIMS 2002]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» D. If the assertion and reason both are false.

Discussion

22.	Assertion : Owls can move freely during night. Reason : They have large number of rods on their retina. [AIIMS 2003]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» D. If the assertion and reason both are false.

Discussion

23.	Assertion : The stars twinkle while the planets do not. Reason : The stars are much bigger in size than the planets. [AIIMS 2003]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
Answer» C. If assertion is true but reason is false.

Discussion

24.	Assertion : A red object appears dark in the yellow light Reason : A red colour is scattered less [AIIMS 2004]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false
D.	If the assertion and reason both are false.
Answer» C. If assertion is true but reason is false

Discussion

25.	A thin prism of glass is placed in air and water successively. If aμg = 3/2 and aμw = 4/3, then the ratio of deviations produced by the prism for a small angle of incidence when placed in air and water is :
A.	9 : 8
B.	4 : 3
C.	3 : 4
D.	4 : 1
Answer» E.

Discussion

26.	A particle moves towards a concave mirror of focal length 30 cm along its axis and with a constant speed of 4 cm/ sec. What is the speed of its image when the particle is at 90 cm from the mirror?
A.	2 cm/ sec.
B.	8 cm/sec.
C.	1 cm/sec.
D.	4 cm/sec.
Answer» D. 4 cm/sec.

Discussion

27.	A prism can produce a minimum deviation d in a light beam. If three such prisms are combined, the minimum deviation that can be produced in this beam is:
A.	0
B.	δ
C.	2δ
D.	3δ
Answer» C. 2δ

Discussion

28.	A ray of light passes through an equilateral prism such that the angle of incidence is equal to the angle of emergence and latter is equal to 3/4th the angle of prism. The angle of deviation is :
A.	45o
B.	39o
C.	20o
D.	30o
Answer» E.

Discussion

29.	spherical convex surface separates object and image space of refractive index 1 and 4/3 respectively. If radius of curvature of the surface is 0.1 m, its power is :
A.	2.5 D
B.	-2.5 D
C.	3.3 D
D.	-3.3 D
Answer» B. -2.5 D

Discussion

30.	A spherical convex surface separates object and image space of refractive index 1 and 4/3 respectively. If radius of curvature of the surface is 0.1 m, its power is :
A.	2.5 D
B.	-2.5 D
C.	3.3 D
D.	-3.3 D
Answer» B. -2.5 D

Discussion

31.	A converging lens is used to form an image on a screen. When the upper half of the lens is covered by an opaque screen :
A.	half of the image will disappear
B.	image will not form on the screen.
C.	intensity of image will increase
D.	intensity of image will decrease
Answer» E.

Discussion

Explore topic-wise MCQs in Maharashtra CET.

&nbsp;Assertion&nbsp;:&nbsp;The&nbsp;size&nbsp;of&nbsp;the&nbsp;mirror&nbsp;affect&nbsp;the&nbsp;nature&nbsp;of&nbsp;the&nbsp;image.&nbsp;Reason&nbsp;:&nbsp;Small&nbsp;mirrors&nbsp;always&nbsp;forms&nbsp;a&nbsp;virtual&nbsp;image.

Assertion&nbsp;:&nbsp;The&nbsp;mirrors&nbsp;used&nbsp;in&nbsp;search&nbsp;lights&nbsp;are&nbsp;parabolic&nbsp;and&nbsp;not&nbsp;concave&nbsp;spherical.&nbsp;Reason&nbsp;:&nbsp;In&nbsp;a&nbsp;concave&nbsp;spherical&nbsp;mirror&nbsp;the&nbsp;image&nbsp;formed&nbsp;is&nbsp;always&nbsp;virtual.

Assertion&nbsp;:&nbsp;The&nbsp;fluorescent&nbsp;tube&nbsp;is&nbsp;considered&nbsp;better&nbsp;than&nbsp;an&nbsp;electric&nbsp;bulb.&nbsp;Reason&nbsp;:&nbsp;Efficiency&nbsp;of&nbsp;fluorescent&nbsp;tube&nbsp;is&nbsp;more&nbsp;than&nbsp;the&nbsp;efficiency&nbsp;of&nbsp;electric&nbsp;bulb.

&nbsp;Assertion&nbsp;:&nbsp;The&nbsp;colour&nbsp;of&nbsp;the&nbsp;green&nbsp;flower&nbsp;seen&nbsp;through&nbsp;red&nbsp;glass&nbsp;appears&nbsp;to&nbsp;be&nbsp;dark.&nbsp;Reason&nbsp;:&nbsp;Red&nbsp;glass&nbsp;transmits&nbsp;only&nbsp;red&nbsp;light.&nbsp;[AIIMS&nbsp;1997]

Assertion&nbsp;:&nbsp;Different&nbsp;colours&nbsp;travel&nbsp;with&nbsp;different&nbsp;speed&nbsp;in&nbsp;vacuum.&nbsp;Reason&nbsp;:&nbsp;Wavelength&nbsp;of&nbsp;light&nbsp;depends&nbsp;on&nbsp;refractive&nbsp;index&nbsp;of&nbsp;medium.&nbsp;[AIIMS&nbsp;1998]

Assertion&nbsp;:&nbsp;The&nbsp;setting&nbsp;sun&nbsp;appears&nbsp;to&nbsp;be&nbsp;red.&nbsp;Reason&nbsp;:&nbsp;Scattering&nbsp;of&nbsp;light&nbsp;is&nbsp;directly&nbsp;proportional&nbsp;to&nbsp;the&nbsp;wavelength.&nbsp;[AIIMS&nbsp;2000]

Assertion&nbsp;:&nbsp;Blue&nbsp;colour&nbsp;of&nbsp;sky&nbsp;appears&nbsp;due&nbsp;to&nbsp;scattering&nbsp;of&nbsp;blue&nbsp;colour.&nbsp;Reason&nbsp;:&nbsp;Blue&nbsp;colour&nbsp;has&nbsp;shortest&nbsp;wave&nbsp;length&nbsp;in&nbsp;visible&nbsp;spectrum.&nbsp;[AIIMS&nbsp;2001]

Assertion&nbsp;:&nbsp;The&nbsp;air&nbsp;bubble&nbsp;shines&nbsp;in&nbsp;water.&nbsp;Reason&nbsp;:&nbsp;Air&nbsp;bubble&nbsp;in&nbsp;water&nbsp;shines&nbsp;due&nbsp;to&nbsp;refraction&nbsp;of&nbsp;light&nbsp;[AIIMS&nbsp;2002]

Assertion&nbsp;:&nbsp;Owls&nbsp;can&nbsp;move&nbsp;freely&nbsp;during&nbsp;night.&nbsp;Reason&nbsp;:&nbsp;They&nbsp;have&nbsp;large&nbsp;number&nbsp;of&nbsp;rods&nbsp;on&nbsp;their&nbsp;retina.&nbsp;[AIIMS&nbsp;2003]

Assertion&nbsp;:&nbsp;The&nbsp;stars&nbsp;twinkle&nbsp;while&nbsp;the&nbsp;planets&nbsp;do&nbsp;not.&nbsp;Reason&nbsp;:&nbsp;The&nbsp;stars&nbsp;are&nbsp;much&nbsp;bigger&nbsp;in&nbsp;size&nbsp;than&nbsp;the&nbsp;planets.&nbsp;[AIIMS&nbsp;2003]

Assertion&nbsp;:&nbsp;A&nbsp;red&nbsp;object&nbsp;appears&nbsp;dark&nbsp;in&nbsp;the&nbsp;yellow&nbsp;light&nbsp;Reason&nbsp;:&nbsp;A&nbsp;red&nbsp;colour&nbsp;is&nbsp;scattered&nbsp;less&nbsp;[AIIMS&nbsp;2004]

A&nbsp;prism&nbsp;can&nbsp;produce&nbsp;a&nbsp;minimum&nbsp;deviation&nbsp;d&nbsp;in&nbsp;a&nbsp;light&nbsp;beam.&nbsp;If&nbsp;three&nbsp;such&nbsp;prisms&nbsp;are&nbsp;combined,&nbsp;the&nbsp;minimum&nbsp;deviation&nbsp;that&nbsp;can&nbsp;be&nbsp;produced&nbsp;in&nbsp;this&nbsp;beam&nbsp;is:

A&nbsp;converging&nbsp;lens&nbsp;is&nbsp;used&nbsp;to&nbsp;form&nbsp;an&nbsp;image&nbsp;on&nbsp;a&nbsp;screen.&nbsp;When&nbsp;the&nbsp;upper&nbsp;half&nbsp;of&nbsp;the&nbsp;lens&nbsp;is&nbsp;covered&nbsp;by&nbsp;an&nbsp;opaque&nbsp;screen&nbsp;:

Assertion : The size of the mirror affect the nature of the image. Reason : Small mirrors always forms a virtual image.

Assertion : The mirrors used in search lights are parabolic and not concave spherical. Reason : In a concave spherical mirror the image formed is always virtual.

Assertion : The fluorescent tube is considered better than an electric bulb. Reason : Efficiency of fluorescent tube is more than the efficiency of electric bulb.

Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light. [AIIMS 1997]

Assertion : Different colours travel with different speed in vacuum. Reason : Wavelength of light depends on refractive index of medium. [AIIMS 1998]

Assertion : The setting sun appears to be red. Reason : Scattering of light is directly proportional to the wavelength. [AIIMS 2000]

Assertion : Blue colour of sky appears due to scattering of blue colour. Reason : Blue colour has shortest wave length in visible spectrum. [AIIMS 2001]

Assertion : The air bubble shines in water. Reason : Air bubble in water shines due to refraction of light [AIIMS 2002]

Assertion : Owls can move freely during night. Reason : They have large number of rods on their retina. [AIIMS 2003]

Assertion : The stars twinkle while the planets do not. Reason : The stars are much bigger in size than the planets. [AIIMS 2003]

Assertion : A red object appears dark in the yellow light Reason : A red colour is scattered less [AIIMS 2004]

A prism can produce a minimum deviation d in a light beam. If three such prisms are combined, the minimum deviation that can be produced in this beam is:

A converging lens is used to form an image on a screen. When the upper half of the lens is covered by an opaque screen :