Question 1: Palette 1/83

NEET 2026 MCQ

A ray of monochromatic light is passing through an equilateral prism $(A B C)$ as shown in the figure. The refracted ray $(Q R)$ is parallel to its base $(B C)$ and the angle of incidence $(i)$ is $50^{\circ}$. Then the angle of deviation $(\delta)$ is:

A

$45^{\circ}$

B

$35^{\circ}$

C

$40^{\circ}$

D

$55^{\circ}$

Question 2: Palette 2/83

NEET 2026 MCQ

In a concave lens, a ray of light emanating from the object parallel to the principal axis of the lens after refraction:

A

passes through $2 F$, which is the radius of curvature of the lens.

B

appears to diverge from the first principal focus.

C

emerges parallel to the principal axis.

D

passes through the second principal focus.

Question 3: Palette 3/83

NEET 2026 MCQ

Consider three media $P, Q$ and $R$ with refractive indices $1,1.25$, and 1.5 respectively. The medium $Q$ having a thickness of 5 cm is placed between extended media $P$ and $R$ as shown in the figure. An object $O$ is placed at the centre of medium $Q$. If viewed from medium $P$ near the normal direction, the apparent depth of $O$ is $h_1$. For similar observation from medium $R$, the apparent depth is $h_2$. The value of $\left|h_1-h_2\right|$, in cm , is:

A

3

B

0

C

1

D

2

Question 4: Palette 4/83

NEET 2026 MCQ

The lens combination as shown in the figure, consists of two lenses, $L_1$ and $L_2$, of the focal lengths +10 cm and -10 cm , respectively. The position of the image formed is:

A

60 cm to the right of the concave lens

B

20 cm to the left of the concave lens

C

60 cm to the left of the concave lens

D

30 cm to the right of the concave lens

Question 5: Palette 5/83

NEET 2026 MCQ

Which of the following measurements require 'index correction'?

A

Measurement of speed of sound using resonance tube

B

Measurement of resistance of a wire using meter bridge

C

Measurement of gravitational acceleration using simple pendulum

D

Measurement of focal length of lenses using optical bench

Question 6: Palette 6/83

NEET 2025 MCQ

A microscope has an objective of focal length 2 cm , eyepiece of focal length 4 cm and the tube length of 40 cm . If the distance of distinct vision of eye is 25 cm , the magnification in the microscope is

A

150

B

250

C

100

D

125

Question 7: Palette 7/83

NEET 2025 MCQ

In a certain camera, a combination of four similar thin convex lenses are arranged axially in contact. Then the power of the combination and the total magnification in comparison to the power ( $p$ ) and magnification ( $m$ ) for each lens will be, respectively

A

$4 p$ and $m^4$

B

$p^4$ and $m^4$

C

$4 p$ and $4 m$

D

$p^4$ and $4 m$

Question 8: Palette 8/83

NEET 2024 MCQ

Given below are two statements:

Statement I : Image formation needs regular reflection and/or refraction.

Statement II : The variety in colour of objects we see around us is due to the constituent colours of the light incident on them.

In the light of the above statements, choose the most appropriate answer from the options given below :

A

Statement I is correct but statement II is incorrect

B

Statement I is incorrect but Statement II is correct

C

Both Statement I and Statement II are correct

D

Both Statement I and Statement II are incorrect

Question 9: Palette 9/83

NEET 2024 MCQ

A light ray enters through a right angled prism at point $P$ with the angle of incidence $30^{\circ}$ as shown in figure. It travels through the prism parallel to its base $B C$ and emerges along the face $A C$. The refractive index of the prism is:

A

$ \frac{\sqrt{5}}{4} $

B

$ \frac{\sqrt{5}}{2} $

C

$ \frac{\sqrt{3}}{4} $

D

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

Question 10: Palette 10/83

NEET 2024 MCQ

A small telescope has an objective of focal length $140 \mathrm{~cm}$ and an eye piece of focal length $5.0 \mathrm{~cm}$. The magnifying power of telescope for viewing a distant object is:

A

34

B

28

C

17

D

32

Question 11: Palette 11/83

NEET 2023 MCQ

A lens is made up of 3 different transparent media as shown in figure. A point object O is placed on its axis beyond $2f$. How many real images will be obtained on the other side?

A

2

B

1

C

No image will be formed

D

3

Question 12: Palette 12/83

NEET 2023 MCQ

$\epsilon_0$ and $\mu_0$ are the electric permittivity and magnetic permeability of free space respectively. If the corresponding quantities of a medium are $2 ~\epsilon_0$ and $1.5 ~\mu_0$ respectively, the refractive index of the medium will nearly be :

A

$\sqrt{2}$

B

$\sqrt{3}$

C

3

D

2

Question 13: Palette 13/83

NEET 2023 MCQ

A horizontal ray of light is incident on the right angled prism with prism angle $6^{\circ}$. If the refractive index of the material of the prism is 1.5 , then the angle of emergence will be:

A

$9^{\circ}$

B

$10^{\circ}$

C

$4^{\circ}$

D

$6^{\circ}$

Question 14: Palette 14/83

NEET 2023 MCQ

An object is mounted on a wall. Its image of equal size is to be obtained on a parallel wall with the help of a convex lens placed between these walls. The lens is kept at distance x in front of the second wall. The required focal length of the lens will be :

A

less than $\frac{x}{4}$

B

more than $\frac{x}{4}$ but less than $\frac{x}{2}$

C

$\frac{x}{2}$

D

$\frac{x}{4}$

Question 15: Palette 15/83

NEET 2023 MCQ

Light travels a distance $\mathrm{x}$ in time $t_{1}$ in air and $10 \mathrm{x}$ in time $t_{2}$ in another denser medium. What is the critical angle for this medium?

A

$\sin ^{-1}\left(\frac{10 \mathrm{t}_{2}}{\mathrm{t}_{1}}\right)$

B

$\sin ^{-1}\left(\frac{t_{1}}{10 t_{2}}\right)$

C

$\sin ^{-1}\left(\frac{10 t_{1}}{t_{2}}\right)$

D

$\sin ^{-1}\left(\frac{t_{2}}{t_{1}}\right)$

Question 16: Palette 16/83

NEET 2023 MCQ

In the figure shown here, what is the equivalent focal length of the combination of lenses (Assume that all layers are thin) ?

A

$-40 \mathrm{~cm}$

B

$-100 \mathrm{~cm}$

C

$-50 \mathrm{~cm}$

D

$40 \mathrm{~cm}$

Question 17: Palette 17/83

NEET 2023 MCQ

Two thin lenses are of same focal lengths $(f)$, but one is convex and the other one is concave. When they are placed in contact with each other, the equivalent focal length of the combination will be :

A

$f / 4$

B

$f / 2$

C

Infinite

D

Zero

Question 18: Palette 18/83

NEET 2022 MCQ

During a cloudy day, a primary and a secondary rainbow may be created, then the :

A

secondary rainbow is due to single internal reflection and is formed above the primary one.

B

primary rainbow is due to double internal reflection and is formed above the secondary one.

C

primary rainbow is due to double internal reflection and is formed below the secondary one.

D

secondary rainbow is due to double internal reflection and is formed above the primary one.

Question 19: Palette 19/83

NEET 2022 MCQ

An astronomical refracting telescope is being used by an observer to observe planets in normal adjustment. The focal lengths of the objective and eye piece used in the construction of the telescope are 20 m and 2 cm respectively. Consider the following statements about the telescope :

(a) The distance between the objective and eye piece is 20.02 m

(b) The magnification of the telescope is ($-$) 1000

(c) The image of the planet is erect and diminished

(d) The aperture of eye piece is smaller than that of objective

The correct statements are :

A

(a), (b) and (d)

B

(a), (b) and (c)

C

(b), (c) and (d)

D

(c), (d) and (a)

Question 20: Palette 20/83

NEET 2022 MCQ

A biconvex lens has radii of curvature, 20 cm each. If the refractive index of the material of the lens is 1.5, the power of the lens is

A

+2 D

B

+20 D

C

+5 D

D

Infinity

Question 21: Palette 21/83

NEET 2022 MCQ

A light ray falls on a glass surface of refractive index $\sqrt3$, at an angle 60$^\circ$. The angle between the refracted and reflected rays would be

A

30$^\circ$

B

60$^\circ$

C

90$^\circ$

D

120$^\circ$

Question 22: Palette 22/83

NEET 2022 MCQ

Two transparent media A and B are separated by a plane boundary. The speed of light in those media are 1.5 $\times$ 10⁸ m/s and 2.0 $\times$ 10⁸ m/s, respectively. The critical angle for a ray of light for these two media is

A

sin^$-$1 (0.500)

B

sin^$-$1 (0.750)

C

tan^$-$1 (0.500)

D

tan^$-$1 (0.750)

Question 23: Palette 23/83

NEET 2021 MCQ

Find the value of the angle of emergence from the prism. Refractive index of the glass is $\sqrt 3 $

A

90$^\circ$

B

60$^\circ$

C

30$^\circ$

D

45$^\circ$

Question 24: Palette 24/83

NEET 2021 MCQ

A convex lens 'A' of focal length 20 cm and a concave lens 'B' of focal length 5 cm are kept along the same axis with a distance 'd' between them. If a parallel beam of light falling on 'A' leaves 'B' as a parallel beam, then the distance 'd' in cm will be :

A

30

B

25

C

15

D

50

Question 25: Palette 25/83

NEET 2021 MCQ

A lens of large focal length and large aperture is best suited as an objective of an astronomical telescope since :

A

a large aperture contributes to the quality and visibility of the images.

B

a large area of the objective ensures better light gathering power.

C

a large aperture provides a better resolution.

D

All the above.

Question 26: Palette 26/83

NEET 2021 MCQ

A point object is placed at a distance of 60 cm from a convex lens of focal length 30 cm. If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of 40 cm from it, the final image would be formed at a distance of -

A

20 cm from the plane mirror, it would be a virtual image.

B

20 cm from the lens, it would be a real image.

C

30 cm from the lens, it would be a real image.

D

30 cm from the plane mirror, it would be a virtual image.

Question 27: Palette 27/83

NEET 2020 MCQ

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 :

A

${{2A} \over \mu }$

B

$\mu $A

C

${{\mu A} \over 2}$

D

${A \over {2\mu }}$

Question 28: Palette 28/83

NEET 2020 MCQ

The Brewster's angle i_b for an interface should be :

A

30$^\circ $ < i_b< 45$^\circ $

B

45$^\circ $ < i_b< 90$^\circ $

C

i_b = 90$^\circ $

D

0$^\circ $ < i_b< 30$^\circ $

Question 29: Palette 29/83

NEET 2019 MCQ

In total internal reflection when the angle of incidence is equal to the critical angle for the pair of media in contact, what will be angle of refraction?

A

equal to angle of incidence

B

90^o

C

180^o

D

0^o

Question 30: Palette 30/83

NEET 2019 MCQ

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 F₁. When the space between the two lenses is filled with glycerin (which has the same refractive index (m = 1.5) as that of glass) then the equivalent focal length is F₂. The ratio F₁ : F₂ will be :

A

1 : 2

B

2 : 3

C

3 : 4

D

2 : 1

Question 31: Palette 31/83

NEET 2019 MCQ

Pick the wrong answer in the context with rainbow.

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 32: Palette 32/83

NEET 2018 MCQ

The refractive index of the material of a prism is $\sqrt 2 $ and the angle of the prism is 30°. 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

A

60⁰

B

45⁰

C

30⁰

D

zero

Question 33: Palette 33/83

NEET 2018 MCQ

An astronomical refracting telescope will have large angular magnification and high angular resolution, when it has an objective lens of

A

small focal length and large diameter

B

large focal length and small diameter

C

large focal length and large diameter

D

small focal length and small diameter

Question 34: Palette 34/83

NEET 2018 MCQ

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

A

30 cm away from the mirror

B

36 cm away from the mirror

C

30 cm towards the mirror

D

36 cm towards the mirror

Question 35: Palette 35/83

NEET 2017 MCQ

A thin prism having refracting angle 10^o is made of glass of refractive infex 1.42. This prism is combined with another thin prism of glass of refractive index 1.7. This combination producess dispersion without deviation. The refracting angle of second prism should be

A

6^o

B

8^o

C

10^o

D

4^o

Question 36: Palette 36/83

NEET 2017 MCQ

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

A

${y \over x}$

B

${x \over {2y}}$

C

${x \over {y}}$

D

${y \over {2x}}$

Question 37: Palette 37/83

NEET 2016 MCQ

An air bubble in a glass slab with refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face. The thickness (in cm) of the slab is

A

8

B

10

C

12

D

16

Question 38: Palette 38/83

NEET 2016 MCQ

A person can see clearly objects only when they lie between 50 cm and 400 cm from his eyes . In order to increase the maximum distance of distinct vision to infinity, the type and power of the correcting lens, the person has to use. will be

A

convex, + 2.25 diopter

B

concave, $-$0.25 diopter

C

concave, $-$0.2 diopter

D

convex, + 0.15 diopter

Question 39: Palette 39/83

NEET 2016 MCQ

Two identical glass ($\mu $_g = 3/2) equiconvex lenses of focal length $f$ each are kept in contact. The space between the two lenses is filled with water $\left( {{\mu _w} = 4/3} \right)$. The focal length of the combination is

A

$f/3$

B

$f$

C

$4f/3$

D

$3f/4$

Question 40: Palette 40/83

NEET 2016 MCQ

Match the corresponding entries of column 1 with column 2. [Where m is the magnification produced by the mirror]

Column 1			Column 2
(A)	m = - 2		(p)	Convex mirror
(B)	m = -${1 \over 2}$		(q)	Concave mirror
(C)	m = +2		(r)	Real image
(D)	m = +${1 \over 2}$		(s)	Virtual image

A

A  $ \to $  p   and   s;   B $ \to $ q and r;   C $ \to $ q and s;   D $ \to $ q and r

B

A  $ \to $  r   and   s;   B $ \to $ q and s;   C $ \to $ q and r;   D $ \to $ p and s

C

A  $ \to $  q  and  r;   B $ \to $ q and r;   C $ \to $ q and s;   D $ \to $ p and s

D

A  $ \to $  p   and   r;   B $ \to $ p and s;   C $ \to $ p and q;   D $ \to $ r and s

Question 41: Palette 41/83

NEET 2016 MCQ

The angle of incidence for a ray of light at a refracting surface of a prism is 45^o. The angle of prism is 60^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

A

${45^o};\sqrt 2 $

B

${30^o};{1 \over {\sqrt 2 }}$

C

${45^o};{1 \over {\sqrt 2 }}$

D

${30^o};\sqrt 2 $

Question 42: Palette 42/83

NEET 2016 MCQ

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

A

50.0 cm

B

54.0 cm

C

37.3 cm

D

46.0 cm

Question 43: Palette 43/83

NEET 2015 MCQ

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

A

${{L + I} \over {L - I}}$

B

${L \over I}$

C

${L \over I} + 1$

D

${L \over I} - 1$

Question 44: Palette 44/83

NEET 2015 MCQ

A beam of light consisting of red, green and blue colours is incifent 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.


The prism will

A

not separate the three colours at all

B

separate the red colour part from the green and blue colours

C

separate the blue colour part from the red and green colours

D

separate all the three colours from one another

Question 45: Palette 45/83

NEET 2015 MCQ

Two identical thin plano-convex glass lenses (refractive index 1.5) each having radius of curvature of 20 cm are placed with 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

A

$-$ 50 cm

B

50 cm

C

$-$ 20 cm

D

$-$ 25 cm

Question 46: Palette 46/83

NEET 2015 MCQ

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

A

90^o $-$ A

B

180^o + 2A

C

180^o $-$ 3A

D

180^o $-$ 2A

Question 47: Palette 47/83

NEET 2014 MCQ

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

A

2sinA

B

2cosA

C

${1 \over 2}$cosA

D

tanA

Question 48: Palette 48/83

NEET 2014 MCQ

If the focal length of objective lens is increased then magnifying power of

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 49: Palette 49/83

NEET 2013 MCQ

Two plane mirrors are inclined at 70^o. A ray incident on one mirror at angle, $\theta $ after reflection falls on second mirror and is reflected from there parallel to first mirror. The value of $\theta $ is

A

45^o

B

30^o

C

55^o

D

50^o

Question 50: Palette 50/83

NEET 2013 MCQ

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

A

${R \over {\left( {{\mu _1} - {\mu _2}} \right)}}$

B

${{2R} \over {\left( {{\mu _2} - {\mu _1}} \right)}}$

C

${R \over {2\left( {{\mu _1} + {\mu _2}} \right)}}$

D

${R \over {2\left( {{\mu _1} - {\mu _2}} \right)}}$

Question 51: Palette 51/83

NEET 2013 MCQ

For a normal eye, the cornea of eye provides a converging power of 40 D and the least converging power of the eye lens behinf the cornea is 20 D. Using this information, the distance between the retina and the cornea-eye lens can be estimated to be

A

1.67 cm

B

1.5 cm

C

5 cm

D

2.5 cm

Question 52: Palette 52/83

NEET 2012 MCQ

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.

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 53: Palette 53/83

NEET 2012 MCQ

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 enf closer to the pole is 20 cm away from the mirror. The length of the image is

A

10 cm

B

15 cm

C

2.5 cm

D

5 cm

Question 54: Palette 54/83

NEET 2012 MCQ

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

A

equal to that of glass

B

less than one

C

greater than that of glass

D

less than that of glass

Question 55: Palette 55/83

NEET 2012 MCQ

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 equal

A

${f_1} + {f_2}$

B

$-$${f_1} + {f_2}$

C

2${f_1} + {f_2}$

D

$-$2${f_1} + {f_2}$

Question 56: Palette 56/83

NEET 2012 MCQ

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

A

$\mu $A

B

${{\mu A} \over 2}$

C

${A \over \mu }$

D

${A \over {2\mu }}$

Question 57: Palette 57/83

NEET 2012 MCQ

The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20 cm. The focal length of lenses are

A

10 cm, 10 cm

B

15 cm, 5 cm

C

18 cm, 2 cm

D

11 cm, 9 cm

Question 58: Palette 58/83

NEET 2011 MCQ

A converging beam of rays is incident on a diverging lens. Having passed through 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 meet will move 5 cm closer to the lens. The focal length of the lens is

A

5 cm

B

$-$ 10 cm

C

20 cm

D

$-$ 30 cm

Question 59: Palette 59/83

NEET 2011 MCQ

A thin prism of angle 15^o 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 prisms produces dispersion without deviation. The angle of the second prism should be

A

5^o

B

7^o

C

10^o

D

12^o

Question 60: Palette 60/83

NEET 2011 MCQ

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 ?

A

Virtual, upright, height = 1 cm

B

Virtual, upright, height = 0.5 cm

C

Real, inverted, height = 4 cm

D

Real, inverted, height = 1 cm

Question 61: Palette 61/83

NEET 2011 MCQ

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

A

Working of optical fibre

B

difference between apparent and real depth of a pond

C

Mirage on hot summer days

D

Brilliance of diamond

Question 62: Palette 62/83

NEET 2010 MCQ

The speed of light in media M₁ and M₂ are 1.5 $ \times $ 10⁸ m/s and 2.0 $ \times $ 10⁸ m/s respectively. A ray of light enters from medium M₁ to M₂ at an incidence angle i. If the rays suffers total internal reflection, the value of i is

A

Equal to sin^$-$1 $\left( {{2 \over 3}} \right)$

B

Equal to or less than sin^$-$1$\left( {{3 \over 5}} \right)$

C

Equal to or greater than sin^$-$1 $\left( {{3 \over 4}} \right)$

D

Less than sin^$-$1$\left( {{2 \over 3}} \right)$

Question 63: Palette 63/83

NEET 2010 MCQ

A rays of light is incident on a 60^o prism at the minimum deviation position. The angle of refraction at the first face (i.e., incident face) of the prism is

A

zero

B

30^o

C

45^o

D

60^o

Question 64: Palette 64/83

NEET 2010 MCQ

A lens having focal length f and aperture of diameter d forms an image of intensity I. Aperture of diameter ${d \over 2}$ in central region of lens is covered by a black paper. Focal length of lens and intensity of image now will be respectively

A

$f\,$ and ${I \over 4}$

B

${{3f} \over 4}$ and ${I \over 2}$

C

$f$ and ${{3I} \over 4}$

D

${f \over 2}$ and ${I \over 2}$

Question 65: Palette 65/83

NEET 2010 MCQ

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^o. For which of the following value of $\mu $ the ray can undergo total internal reflection ?

A

$\mu $ = 1.33

B

$\mu $ = 1.40

C

$\mu $ = 1.50

D

$\mu $ = 1.25

Question 66: Palette 66/83

NEET 2008 MCQ

Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial. The power of the combination is

A

${{{f_1} + {f_2}} \over 2}$

B

${{{f_1} + {f_2}} \over {{f_1}{f_2}}}$

C

$\sqrt {{{{f_1}} \over {{f_2}}}} $

D

$\sqrt {{{{f_2}} \over {{f_1}}}} $

Question 67: Palette 67/83

NEET 2008 MCQ

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 $ 10⁹ m and its mean distance from the earth is 1.5 $ \times $ 10¹¹ m. What is the diameter of the sun's image on the paper ?

A

6.5 $ \times $10^$-$5 m

B

12.4 $ \times $10^$-$4 m

C

9.2 $ \times $10^$-$4 m

D

6.5 $ \times $10^$-$4 m

Question 68: Palette 68/83

NEET 2007 MCQ

A small coin is resting on the bottom of a beaker filled with liquid . A ray of light from the coin travels upto the surface of the liquid and moves along its surface. How fast is the light travelling in the liquid ?

A

2.4 $ \times $ 10⁸ m/s

B

3.0 $ \times $ 10⁸ m/s

C

1.2 $ \times $ 10⁸ m/s

D

1.8 $ \times $ 10⁸ m/s

Question 69: Palette 69/83

NEET 2006 MCQ

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 power in diopters of the combination is

A

zero

B

25

C

50

D

infinite.

Question 70: Palette 70/83

NEET 2006 MCQ

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 ?

A

2 cm upward

B

1 cm upward

C

4.5 cm downward

D

1 cm downward

Question 71: Palette 71/83

NEET 2004 MCQ

The refractive index of the material of a prism is $\sqrt 2 $ and its refracting angle is 30^o. 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 with retrace its path after reflection from the mirrored surface if its angle of incidence on the prism is

A

45^o

B

60^o

C

0

D

30^o

Question 72: Palette 72/83

NEET 2004 MCQ

A beam of light composed of red and green ray is incident obliquely at a point on the face of rectangular glass slab. When coming out on the opposite parallel face, the red green ray emerge from

A

Two points propagating in two different non 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 firections.

Question 73: Palette 73/83

NEET 2003 MCQ

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

A

$f' = f,f'' = 2f$

B

$f' = 2f,f'' = f$

C

$f' = f,f'' = f$

D

$f' = 2f,f'' = 2f$

Question 74: Palette 74/83

NEET 2003 MCQ

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

A

become zero

B

become infinite

C

become small, but non-zero

D

remain unchanged

Question 75: Palette 75/83

NEET 2002 MCQ

A bulb is located on a wall. Its image is to be obtained on a parallel wall with the help of convex lens. The lens is placed at a distance d ahead of second wall, then required focal length will be

A

only ${d \over 4}$

B

only ${d \over 2}$

C

more than ${d \over 4}$ but less than ${d \over 2}$

D

less than ${d \over 4}$

Question 76: Palette 76/83

NEET 2002 MCQ

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 meter from eye. The wavelength of light is 5000 $\mathop A\limits^ \circ $

A

2.32 m

B

4.28 mm

C

1.25 cm

D

12.48 cm

Question 77: Palette 77/83

NEET 2002 MCQ

For the given incident ray as shown in figure, the condition of total internal refraction of this ray the required refractive index of prism will be

A

${{\sqrt 3 + 1} \over 2}$

B

${{\sqrt 2 + 1} \over 2}$

C

$\sqrt {{3 \over 2}} $

D

$\sqrt {{7 \over 6}} $

Question 78: Palette 78/83

NEET 2001 MCQ

A disc is placed on a surface of pond which has refractive index 5/3. A source of light is placed 4 m below the surface of liquid. The minimum radius of disc needed so that light is not coming out is,

A

$\infty $

B

3 m

C

6 m

D

4 m

Question 79: Palette 79/83

NEET 2001 MCQ

Optical fibre are based on

A

total internal reflection

B

less scattering

C

refraction

D

less absorption coefficient.

Question 80: Palette 80/83

NEET 2000 MCQ

A tall man of height 6 feet, want to see his full image. Then required minimum length of the mirror will be

A

12 feet

B

3 feet

C

6 feet

D

any length

Question 81: Palette 81/83

NEET 2000 MCQ

For a plano convex lens ($\mu $ = 1.5) has radius of curvature 10 cm. It is silvered on its plane surface. Find focal length after silvering

A

10 cm

B

20 cm

C

15 cm

D

25 cm

Question 82: Palette 82/83

NEET 2000 MCQ

A bubble in glass slab ($\mu $ = 1.5) when viewed from one side appears at 5 cm and 2 cm from other side, then thickness of slab is

A

3.75 cm

B

3 cm

C

10.5 cm

D

2.5 cm.

Question 83: Palette 83/83

NEET 2000 MCQ

Rainbow is formed due to

A

scattering and refraction

B

internal reflection and dispersion

C

reflection only

D

diffraction and dispersion.