# Solved papers for NEET Physics Ray Optics NEET PYQ-Ray Optics

### done NEET PYQ-Ray Optics Total Questions - 62

• question_answer1) A luminous object is placed at a distance of 30 cm from the convex lens of focal length 20 cm. On the other side of the lens, at what distance from the lens, a convex mirror of radius of curvature 10 cm, be placed in order to have an upright image of the object coincident with it?   [AIPMT 1998]

A)
12 cm

B)
30 cm

C)
50 cm

D)
60 cm

• question_answer2) Light enters at an angle of incidence in a transparent rod of refractive index n. For what value of the refractive index of the material of the rod the light once entered into it will not leave it through its lateral face whatsoever be the value of angle of incidence?                     [AIPMT 1998]

A)
$n>\sqrt{2}$

B)
$n=1$

C)
$n=1.1$

D)
$n=1.3$

• question_answer3) A plano-convex lens is made of material of refractive index 1.6. The radius of curvature of the curved surface is 60 cm. The focal length of the lens is:                                           [AIPMT 1999]

A)
50 cm

B)
100 cm

C)
200 cm

D)
400 cm

• question_answer4) The refractive index of the material of the prism is $\sqrt{3},$ then the angle of minimum deviation of the prism is :                             [AIPMT 1999]

A)
${{30}^{o}}$

B)
${{45}^{o}}$

C)
${{60}^{o}}$

D)
${{75}^{o}}$

• question_answer5) Two sources are at a finite distance apart. They emit sounds of wavelength $\lambda$. An observer situated between them on line joining approaches one source with speed u. Then the number of beats heard/s by observer will be: [AIPMT 2000]

A)
$\frac{2u}{\lambda }$

B)
$\frac{u}{\lambda }$

C)
$\frac{u}{2\lambda }$

D)
$\frac{\lambda }{u}$

• question_answer6) Rainbows are formed by:            [AIPMT 2000]

A)
reflection and diffraction

B)
refraction and scattering

C)
dispersion and total internal reflection

D)
interference only

• question_answer7) A man is 6 feet tall. In order to see his entire image, he requires a plane mirror of minimum length equal to:

A)
6 ft

B)
12 ft

C)
2 ft

D)
3 ft

• question_answer8) A plano-convex lens is made of a material of refractive index $\mu =1.5$. The radius of curvature of curved surface of the lens is 20 cm. If its plane surface is silvered, the focal length of the silvered lens will be:      [AIPMT 2000]

A)
10 cm

B)
20 cm

C)
40 cm

D)
80 cm

• question_answer9)   A transparent cube contains a small air bubble. Its apparent distance is 2 cm when seen through one face and 5 cm when seen through other face. If the refractive index of the material of the cube is 1.5, the real length of the edge of cube must be: [AIPMT 2000]

A)
7 cm

B)
7.5 cm

C)
10.5 cm

D)
$\frac{14}{3}\,cm$

• question_answer10) A wave enters to water from air. In air frequency, wavelength, intensity and velocity are ${{n}_{1}},\,{{\lambda }_{1}},\,{{I}_{1}}$ and ${{v}_{1}}$ respectively. In water the corresponding quantities are ${{n}_{2}},\,{{\lambda }_{2}},\,{{I}_{2}}$ and ${{v}_{2}}$ respectively; then: [AIPMT 2001]

A)
${{I}_{1}}={{I}_{2}}$

B)
${{n}_{1}}={{n}_{2}}$

C)
${{v}_{1}}={{v}_{2}}$

D)
${{\lambda }_{1}}={{\lambda }_{2}}$

• question_answer11) Transmission of light in optical fibre is due to: [AIPMT 2001]

A)
scattering

B)
diffraction

C)
polarisation

D)
multiple total internal reflections

• question_answer12) Refractive index of water is 5/3. A light source is placed in water at a depth of 4 m. Then what must be the minimum radius of disc placed on water surface so that the light of source can be stopped? [AIPMT 2001]

A)
3 m

B)
4 m

C)
5 m

D)
$\infty$

• question_answer13)             Diameter of human eye lens is 2 mm. What will be the minimum distance between two points to resolve them, which are situated at a distance of 50 m from eye? The wavelength of light is $5000\text{ }{\AA}$:                             [AIPMT 2002]

A)
2.32 m

B)
4.28 mm

C)
1.25 cm

D)
12.48 cm

• question_answer14) A body is located on a wall. Its image of equal size is to be obtained on a parallel wall with the help of a convex lens. The lens is placed at a distance d ahead of second wall, then the required focal length will be:                        [AIPMT 2002]

A)
only $\frac{d}{4}$

B)
only$\frac{d}{2}$

C)
more than $\frac{d}{4}$ but less than $\frac{d}{2}$

D)
less than $\frac{d}{4}$

• question_answer15)  For the given incident ray as shown in figure, the condition of total internal reflection of the ray will be satisfied if the refractive index of block will be:                                                                              [AIPMT 2002]

A)
$\frac{\sqrt{3}+1}{2}$

B)
$\frac{\sqrt{2}+1}{2}$

C)
$\sqrt{\frac{3}{2}}$

D)
$\sqrt{\frac{7}{6}}$

• question_answer16)  An equiconvex lens is cut into two halves along (i) XOX' and (ii) YOY' as shown in the figure. Let $f,\,f',\,f''$ be the focal lengths of the complete lens, of each half in case (i), and of each half in case (ii), respectively. Choose the correct statement from the following:                                                     [AIPMT 2003]

A)
$f'=f,\,\,f''=f$

B)
$f'=2f,\,\,f''=2f$

C)
$f'=f,\,\,f''=2f$

D)
$f'=2f,\,\,f''=f$

• question_answer17) A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will:  [AIPMT 2003]

A)
become small, but non-zero

B)
remain unchanged

C)
become zero

D)
become infinite

• question_answer18) A beam of light composed of red and green rays is incident obliquely at a point on the face of a rectangular glass slab. When coming out on the opposite parallel face, the red and green rays emerge from:                [AIPMT (S) 2004]

A)
two points propagating in two different on-parallel directions

B)
two points propagating in two different parallel directions

C)
one point propagating in two different directions

D)
one point propagating in the same direction

• question_answer19) The refractive index of the material of a prism is $\sqrt{2}$ and its refracting angle is $30{}^\circ$. One of the refracting surfaces of the prism is made a mirror inwards. A beam of monochromatic light entering the prism from the other face will retrace its path after reflection from the mirrored surface if its angle of incidence on the prism is: [AIPMT (S) 2004]

A)
$45{}^\circ$

B)
$60{}^\circ$

C)
$0{}^\circ$

D)
$30{}^\circ$

• question_answer20) A telescope has an objective lens of 10 cm diameter and is situated at a distance of one kilometre from two objects. The minimum distance between these two objects, which can be resolved by the telescope, when the mean wavelength of light is  $5000\text{ }{\AA},$ of the order of: [AIPMT (S) 2004]

A)
0.5 m

B)
5 m

C)
5 mm

D)
5 cm

• question_answer21) The angular resolution of a 10 cm diameter telescope at a wavelength of $5000\text{ }{\AA}$ is of the -order of:                        [AIPMT (S) 2005]

A)
${{10}^{6}}\,\text{rad}$

B)
${{10}^{-2}}\,\text{rad}$

C)
${{10}^{-4}}\,\text{rad}$

D)
${{10}^{-6}}\,\text{rad}$

• question_answer22) Two vibrating tuning forks produce progressive waves given by ${{y}_{1}}=4\sin 500\,\pi t$ and${{y}_{2}}=2\sin \,506\,\pi t$. Number of beats produced per minute is:                           [AIPMT (S) 2005]

A)
360

B)
180

C)
3

D)
60

• question_answer23) A microscope is focussed on a mark on a piece of paper and then a slab of glass of thickness 3 cm and refractive index 1.5 is placed over the mark. How should the microscope be moved to get the mark in focus again?            [AIPMT (S) 2006]

A)
1 cm upward

B)
4.5 cm downward

C)
1 cm downward

D)
2 cm upward

• question_answer24) A convex lens and a concave lens, each having same focal length of 25 cm, are put in contact to form a combination of lenses. The powers diopters of the combination is: [AIPMT (S) 2006]

A)
25

B)
50

C)
infinite

D)
zero

• question_answer25)  A small coin is resting on the bottom of a beaker filled with a liquid. A ray of light from the coin travels upto the surface of the liquid and moves along its surface (see figure). [AIPMT (S) 2007] How fast is the light travelling in the liquid?

A)
$1.8\times {{10}^{8}}m/s$

B)
$2.4\times {{10}^{8}}m/s$

C)
$3.0\times {{10}^{8}}m/s$

D)
$1.2\times {{10}^{8}}m/s$

• question_answer26) The frequency of a light wave in a material is $2\times {{10}^{14}}\,Hz$ and wavelength is $5000\text{ }{\AA}$. The refractive index of material will be: [AIPMT (S) 2007]

A)
1.40

B)
1.50

C)
3.00

D)
1.33

• question_answer27) Two thin lenses of focal lengths ${{f}_{1}}$ and ${{f}_{2}}$ are in contact and coaxial. The power of the combination is                          [AIPMPT (S) 2008]

A)
$\sqrt{\frac{{{f}_{1}}}{{{f}_{2}}}}$

B)
$\sqrt{\frac{{{f}_{2}}}{{{f}_{1}}}}$

C)
$\frac{{{f}_{1}}+{{f}_{2}}}{{{f}_{1}}{{f}_{2}}}$

D)
$\frac{{{f}_{1}}+{{f}_{2}}}{{{f}_{1}}{{f}_{2}}}$

• question_answer28) A boy is trying to start a fire by focusing sunlight on a piece of paper using an equiconvex lens of focal length 10 cm. The diameter of the sun is $1.39\times {{10}^{9}}m$ and its mean distance from the earth is $1.5\times {{10}^{11}}m$. What is the diameter of the sun's image on the paper?                                  [AIPMPT (S) 2008]

A)
$9.2\times {{10}^{-4}}m$

B)
$6.5\times {{10}^{-4}}m$

C)
$6.5\times {{10}^{-5}}m$

D)
$12.4\times {{10}^{-4}}m$

• question_answer29) A ray of light travelling in a transparent medium of refractive index $\mu$ falls, on a surface separating the medium from air at an angle of incidence of$45{}^\circ$. For which of the following value of p the ray can undergo total internal reflection?   [AIPMT (S) 2010]

A)
$\mu =1.33$

B)
$\mu =1.40$

C)
$\mu =1.50$

D)
$\mu =1.25$

• question_answer30) The speed of light in media ${{M}_{1}}$ and ${{M}_{2}}$ is $1.5\times {{10}^{8}}m/s$ and $2.0\times {{10}^{8}}\,m/s$ respectively. A ray of light enters from medium ${{M}_{1}}$ to ${{M}_{2}}$ at an incidence angle i. If the ray suffers total internal reflection, the value of i is      [AIPMT (M) 2010]

A)
equal to ${{\sin }^{-1}}\left( \frac{2}{3} \right)$

B)
equal to or less than ${{\sin }^{-1}}\left( \frac{3}{5} \right)$

C)
equal to or greater than ${{\sin }^{-1}}\left( \frac{3}{4} \right)$

D)
less than ${{\sin }^{-1}}\left( \frac{2}{3} \right)$

• question_answer31) A ray of light is incident on a $60{}^\circ$ prism at the minimum deviation position. The angle of refraction at the first face (i.e., incident face) of the prism is                               [AIPMT (M) 2010]

A)
zero

B)
${{30}^{o}}$

C)
${{45}^{o}}$

D)
${{60}^{o}}$

• question_answer32) A thin prism of angle $15{}^\circ$ made of glass of refractive index ${{\mu }_{1}}=1.5$ is combined with another prism of glass of refractive index ${{\mu }_{2}}=1.75$. The combination of the prism produces dispersion without deviation. The angle of the second prism should be [AIPMT (M) 2011]

A)
$7{}^\circ$

B)
$10{}^\circ$

C)
$12{}^\circ$

D)
$5{}^\circ$

• question_answer33) A conversing beam of rays is incident on a diverging lens. Having passed though the lens the rays intersect at a point 15 cm from the lens on the opposite side. If the lens is removed the point where the rays meets will move 5 cm closer to the lens. The focal length of the lens is [AIPMT (M) 2011]

A)
- 10 cm

B)
20 cm

C)
- 30 cm

D)
5 cm

• question_answer34)   A biconvex lens has a radius of curvature of magnitude 20 cm. Which one of the following options describe best the image formed of an object of height 2 cm placed 30 cm from the lens?                                   [AIPMT (S) 2011]

A)
Virtual, upright, height $=0.5\text{ }cm$

B)
Real, inverted, height $=4\text{ }cm$

C)
Real, inverted, height $=1\text{ }cm$

D)
Virtual, upright, height $=1\text{ }cm$

• question_answer35) Which of the following is not due to total internal reflection?

A)
Difference between apparent and real depth of a pond

B)
Mirage on hot summer days

C)
Brilliance of diamond

D)
Working of optical fibre

• question_answer36) For the angle of minimum deviation of a prism to be equal to its refracting angle, the prism must be made of a material whose refractive index                                           [AIPMT (M) 2012]

A)
lies between $\sqrt{2}$ and 1

B)
lies between 2 and $\sqrt{2}$

C)
is less than 1

D)
is greater than 2

• question_answer37) A rod of length 10 cm lies along the principal axis of a concave mirror of focal length 10 cm in such a way that its end closer to the pole is 20 cm away from the mirror. The length of the image is [AIPMT (M) 2012]

A)
10 cm

B)
15 cm

C)
2.5 cm

D)
5 cm

• question_answer38) When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index          [AIPMT (S) 2012]

A)
equal to that of glass

B)
less than one

C)
greater than that of glass

D)
less than that of glass

• question_answer39) A ray of light is incident at an angle of incidence, i, on one face of a prism of angle A (assumed to be small) and emerges normally from the opposite face. If the refractive index of the prism is $\mu ,$the angle of incidence i, is nearly equal to                                                                                                               [AIPMT (S) 2012]

A)
$\mu A$

B)
$\frac{\mu A}{2}$

C)
$A/\mu$

D)
$A/2\mu$

• question_answer40) A concave mirror of focal length ${{f}_{1}}$ is placed at a distance of d from a convex lens of focal length ${{f}_{2}}$. A beam of light coming from infinity and falling on this convex lens concave mirror combination returns to infinity. The distance d must be equal                       [AIPMT (S) 2012]

A)
${{f}_{1}}+{{f}_{2}}$

B)
$-{{f}_{1}}+{{f}_{2}}$

C)
$2{{f}_{1}}+{{f}_{2}}$

D)
$-2{{f}_{1}}+{{f}_{2}}$

• question_answer41) A plano-convex lens fits exactly into a plano-concave   lens.   Their   plane surfaces are parallel to each other. If lenses are made of different materials of refractive indices ${{\mu }_{1}}$ and ${{\mu }_{2}}$ and - R  is the radius of curvature of the curved surface of the lenses, then the focal length of the combination is                                [NEET 2013]

A)
$\frac{R}{2({{\mu }_{1}}+{{\mu }_{2}})}$

B)
$\frac{R}{2({{\mu }_{1}}-{{\mu }_{2}})}$

C)
$\frac{R}{({{\mu }_{1}}-{{\mu }_{2}})}$

D)
$\frac{2R}{({{\mu }_{2}}-{{\mu }_{1}})}$

• question_answer42) For a normal eye, the cornea of eye provides a converging power of 40D and the least converging power of the eye lens behind the cornea is 20D. Using this information, the distance between the retina and the cornea-eye lens can be estimated to be            [NEET 2013]

A)
5 cm

B)
2.5 cm

C)
1.67 cm

D)
1.5 cm

• question_answer43) If the focal length of objective lens is increased, then magnifying power of       [NEET 2014]

A)
microscope will increase but that of telescope Decrease

B)
microscope and telescope both will increase

C)
microscope and telescope both will decrease

D)
microscope will decrease but that of telescope will increase

• question_answer44) The angle of a prism is A. One of its refracting surfaces is silvered. Light rays falling at an angle of incidence 2 A on the first surface returns back through the same path after suffering reflection at the silvered surface. The refractive index $\mu ,$ of the prism is                                       [NEET 2014]

A)
$2\sin A$

B)
$2\cos A$

C)
$\frac{1}{2}\cos A$

D)
$\tan A$

• question_answer45) Two identical thin plano-convex glass lenses (refractive index 1.5) each having radius of curvature of 20 cm are placed wait their convex surfaces in contact at the centre. The intervening space is filled with oil of refractive index 1.7 The focal length of the combination is     [NEET  2015]

A)
$-20\,cm$

B)
$-25\,cm$

C)
$-50cm$

D)
$50\,cm$

• question_answer46) The refracting angle of a prism is A, and refractive index of the material of the prism is $\cot \,(A/2)$. The angle of minimum deviation is [NEET  2015]

A)
${{180}^{o}}-3A$

B)
${{180}^{o}}-2A$

C)
${{90}^{o}}-A$

D)
${{180}^{o}}+2A$

• question_answer47) In an astronomical telescope in normal adjustment a straight black line of length L is drawn on inside part of objective lens. The eye-piece forms a real image of this line. The length of this image is I. The magnification of the telescope is                                    [NEET (Re) 2015]

A)
$\frac{L}{l}+1$

B)
$\frac{L}{l}-1$

C)
$\frac{L+1}{L-1}$

D)
$\frac{L}{l}$

• question_answer48)  A beam of light consisting of red, green and blue colours is incident on a right angled prism. The refractive index of the material of the prism for the above red, green and blue wavelengths are 1.39, 1.44 and 1.47, respectively.                                                                                                                                        [NEET (Re) 2015]
The prism will,

A)
separate the blue colour part from the red and green colours

B)
separate all the three colours from one another

C)
not separate the three colours at all

D)
separate the red colour part from the green and blue colours

• question_answer49) The angle of incidence for a ray of light at a refracting surface of a prism is $\text{4}{{\text{5}}^{\text{o}}}$.The angle of prism is $\text{6}{{\text{0}}^{\text{o}}}$. If the ray suffers minimum deviation through the prism, the angle of minimum deviation and refractive index of the material of the prism respectively, are:         [NEET - 2016]

A)
${{45}^{o}},\,\frac{1}{\sqrt{2}}$

B)
${{30}^{\text{o}}}\text{,}\,\sqrt{2}$

C)
${{45}^{\text{o}}}\text{,}\,\sqrt{2}$

D)
${{30}^{o}},\,\frac{1}{\sqrt{2}}$

• question_answer50) A astronomical telescope has objective and eyepiece of focal lengths 40 cm and 4 cm respectively. To view an object 200 cm away from the objective, the lenses must be separated by a distance                         [NEET - 2016]

A)
37.3 cm

B)
46.0 cm

C)
50.0 cm

D)
54.0 cm

Match the corresponding entries of column-1 with coloumn-2 (Where m is the magnification produced by the mirror)            [NEET - 2016]
 Column-1 Column-2 $m=2$ 1. Convex mirror $m=-\frac{1}{2}$ 2. Concave mirror $m=+2$ 3. Real image $m=+\frac{1}{2}$ 4. Virtual image

A)
A $\to$ b and c, B $\to$ b and c, C $\to$ b and d, D $\to$ a and  d.

B)
A $\to$ a and c, B $\to$ a and d, C $\to$ a and b, D $\to$ c and d

C)
A $\to$ a and d, B $\to$ b and c, C$\to$ b and d, D $\to$ b and c

D)
A $\to$ c and d, B $\to$ b and d, C $\to$ b and c, D $\to$ a and d

• question_answer52) The ratio of resolving powers of an optical microscope for two wavelengths ${{\lambda }_{1}}=4000\,\overset{o}{\mathop{A}}\,$ and ${{\lambda }_{2}}=6000\,\overset{o}{\mathop{A}}\,$ is [NEET-2017]

A)
16 : 81

B)
8 : 27

C)
9 : 4

D)
3 : 2

• question_answer53) A thin prism having refracting angle ${{10}^{o}}$ is made of glass of refractive index 1.42. This prism is combined with another thin prism of glass of refractive index 1.7. This combination produces dispersion without deviation. The refracting angle of second prism should be                                                                                    [NEET-2017]

A)
${{10}^{o}}$

B)
${{4}^{o}}$

C)
${{6}^{o}}$

D)
${{8}^{o}}$

• question_answer54) A beam of light from a source L is incident normally on a plane mirror fixed at a certain distance x from the source. The beam is reflected back as a spot on a scale placed just above the source L. When the mirror is rotated through a small angle $\theta ,$ the spot of the light is found to move through a distance y on the scale. The angle$\theta$ is given by [NEET-2017]

A)
$\frac{x}{y}$

B)
$\frac{y}{2x}$

C)
$\frac{y}{x}$

D)
$\frac{x}{2y}$

• question_answer55) An astronomical refracting telescope will have large angular magnification and high angular resolution, when it has an objective lens of                                                                                                               [NEET - 2018]

A)
Large focal length and large diameter

B)
Large focal length and small diameter

C)
Small focal length and large diameter

D)
Small focal length and small diameter

• question_answer56) The refractive index of the material of a prism is $\sqrt{2}$ and the angle of the prism is$\text{30 }\!\!{}^\circ\!\!\text{ }$. One of the two refracting surfaces of the prism is made a mirror inwards, by silver coating. A beam of monochromatic light entering the prism from the other face will retrace its path (after reflection from the silvered surface) if its angle of incidence on the prism is                                                                                                   [NEET - 2018]

A)
$\text{30 }\!\!{}^\circ\!\!\text{ }$

B)
$45{}^\circ$

C)
$60{}^\circ$

D)
Zero

• question_answer57) An object is placed at a distance of 40 cm from a concave mirror of focal length 15 cm. If the object is displaced through a distance of 20 cm towards the mirror, the displacement of the image will be                                        [NEET - 2018]

A)
30 cm towards the mirror

B)
36 cm away from the mirror

C)
30 cm away from the mirror

D)
36 cm towards the mirror

• question_answer58) Two similar thin equi-convex lenses, of focal length f each, are kept coaxially in contact with each other such that the focal length of the combination is ${{F}_{1}}$. When the space between the two lenses is filled with glycerin (which has the same refractive index $(\mu =1.5)$ as that of glass) then the equivalent focal length is ${{F}_{2}}$. The ratio ${{F}_{2}}$ :  ${{F}_{1}}$will be:                                                                                    [NEET 2019]

A)
2 : 3

B)
3 : 4

C)
2 : 1

D)
1 : 2

• question_answer59) In total internal reflection when the angle of incidence is equal to the critical angle for the pair of media in contact, what will angle of refraction?                                                                                          [NEET 2019]

A)
Equal to angle of incidence

B)
$90{}^\circ$

C)
$180{}^\circ$

D)
$0{}^\circ$

• question_answer60) Pick the wrong answer in the context with rainbow.                                                             [NEET 2019]

A)
An observer can see a rainbow when his front is towards the sun

B)
Rainbow is a combined effect of dispersion, refraction and reflection of sunlight

C)
When the light rays undergo two internal reflections in a water drop, a secondary rainbow is formed

D)
The order of colours is reversed in the secondary rainbow

• question_answer61) A ray is incident at an angle of incidence i on one surface of a small angle prism (with angle of prism A) and emerges normally from the opposite surface. If the refractive index of the material of the prism is $\mu$, then the angle of incidence is nearly equal to:                                                                                                                    [NEET 2020]

A)
$\frac{2A}{\mu }$

B)
$\mu A$

C)
$\frac{\mu A}{2}$

D)
$\frac{A}{2\mu }$

• question_answer62) Assume that light of wavelength 600 nm is coming from a star. The limit of resolution of telescope whose objective has a diameter of 2 m is:                                                                                               [NEET 2020]

A)
$1.83\times {{10}^{7}}\text{rad}$

B)
$7.32\times {{10}^{7}}\text{rad}$

C)
$6.00\times {{10}^{7}}\text{rad}$

D)
$3.66\times {{10}^{7}}\text{rad}$