Ray Optics · Physics · COMEDK

Start Practice

MCQ (Single Correct Answer)

1
In the normal adjustment of an astronomical telescope, the objective and eyepiece are 36 cm apart. If the magnifying power of the telescope is 8 , find the focal lengths of the objective and eyepiece.
COMEDK 2025 Evening Shift
2
A beam of incident parallel light falls on a diverging lens of focal length 20 cm in magnitude. If a converging lens of focal length 15 cm in magnitude is placed at a distance of 10 cm to the right of the diverging lens on the other side, then, the final image formed is:
COMEDK 2025 Evening Shift
3
An object of height $h$ is placed midway between $f$ and $2 f$ in front of a biconvex lens. A real inverted image is captured on a screen placed a little beyond 2 f on the other side of the lens. If the whole arrangement is immersed in water without disturbing the object, lens and the screen positions, then the new image formed will be
COMEDK 2025 Evening Shift
4
A plano-convex lens made of refractive index 1.5 and having radius of curvature $\mathrm{R}=4 \mathrm{~cm}$ fits exactly into a planoconcave lens made of refractive index 1.3 and having the same radius of curvature $R=4 \mathrm{~cm}$ such that their plane surfaces are parallel to each other. The focal length of the combination is :
COMEDK 2025 Evening Shift
5
A beam of light parallel to the principal axis of a concave and convex lens, first passes through the concave lens of focal length 0.5 m and then through the convex lens of focal length 1.75 m . If the lenses are placed 1.25 apart, which of the given statement is true?
COMEDK 2025 Afternoon Shift
6
When a body of refractive index $\boldsymbol{\mu}=\mathbf{1 . 4}$ is put into a liquid, the body becomes invisible. What would be the refractive index of the medium?
COMEDK 2025 Afternoon Shift
7
A ray of light is travelling from glass of refractive index $\frac{3}{2}$ to water of refractive Index $\frac{4}{3}$. What is the minimum angle of incidence for which no light enters in to the water?
COMEDK 2025 Afternoon Shift
8
The focal lengths of the objective and eyepiece of a compound microscope are 1 cm and 10 cm respectively. Length of the tube is 25 cm . If the final image is formed at infinity , the magnifying power of the microscope is :
COMEDK 2025 Afternoon Shift
9
What is the velocity of light in vacuum if the velocity of light in a medium of refractive index 1.2 is ' v ' $\mathrm{ms}^{-1}$ ?
COMEDK 2025 Afternoon Shift
10
One surface of a lens is convex and the other is concave. If the radii of curvatures are $R$ and $r$ respectively, the lens will be convex if
COMEDK 2025 Morning Shift
11
A convex lens forms a real image of an object with magnification $m_1$. The lens is moved towards the object to obtain another real image of magnification $m_2$. The image distance is increased by $x$. The focal length of the lens is
COMEDK 2025 Morning Shift
12

A telescope has an objective of focal length $$60 \mathrm{~cm}$$ and eyepiece of focal length $$5 \mathrm{~cm}$$. The telescope is focussed for least distance of distinct vision $$300 \mathrm{~cm}$$ away from the object. The magnification produced by the telescope at least distance of distinct vision is

COMEDK 2024 Evening Shift
13

Figure below shows a lens of refractive index, $$\mu=1.4$$. $$C_1$$ and $$C_2$$ are the centres of curvature of the two faces of the lens of radii of curvature $$4 \mathrm{~cm}$$ and $$8 \mathrm{~cm}$$ respectively.

COMEDK 2024 Evening Shift Physics - Ray Optics Question 8 English

The lens behaves as a

COMEDK 2024 Evening Shift
14

When a biconvex lens of glass of refractive index 1.5 is dipped in a liquid, it acts like a plane sheet of paper. This means the refractive index of the liquid is

COMEDK 2024 Evening Shift
15

A hollow prism is filled with water and placed in air. It will deviate the incident rays

COMEDK 2024 Evening Shift
16

An object is placed at a distance of $$12 \mathrm{~cm}$$ from a convex lens on its principal axis and a virtual image of certain size is formed. If the object is moved $$4 \mathrm{~cm}$$ away from the lens, a real image of the same size as that of the virtual image is formed. The focal length of the lens in $$\mathrm{cm}$$ is

COMEDK 2024 Afternoon Shift
17

To a fish under water, viewing obliquely, a fisherman standing on the bank of a lake looks

COMEDK 2024 Afternoon Shift
18

In a container of height $$21 \mathrm{~cm}$$, certain transparent liquid is taken to a height of $$12 \mathrm{~cm}$$. When seen from above, it appears half filled. The refractive index of the liquid is

COMEDK 2024 Afternoon Shift
19

Light enters at an angle of incidence in a transparent rod of refractive index '$$n$$'. The least value of '$$n$$' for which the light once entered into it will not leave it through its lateral face whatsoever be the value of the angle of incidence is

COMEDK 2024 Afternoon Shift
20

In the normal adjustment of an astronomical telescope, the objective and eyepiece are $$32 \mathrm{~cm}$$ apart. If the magnifying power of the telescope is 7, find the focal lengths of the objective and eyepiece.

COMEDK 2024 Morning Shift
21

When a particular wave length of light is used the focal length of a convex mirror is found to be $$10 \mathrm{~cm}$$. If the wave length of the incident light is doubled keeping the area of the mirror constant, the focal length of the mirror will be:

COMEDK 2024 Morning Shift
22

For a $$30^{\circ}$$ prism when a ray of light is incident at an angle $$60^{\circ}$$ on one of its faces, the emergent ray passes normal to the other surface. Then the refractive index of the prism is:

COMEDK 2024 Morning Shift
23

A ray of light travelling through a medium of refractive index $$\frac{5}{4}$$ is incident on a glass of refractive index $$\frac{3}{2}$$. Find the angle of refraction in the glass, if the angle of incidence at the given medium - glass interface is $$30^{\circ}$$.

COMEDK 2024 Morning Shift
24

An air bubble in water $$\left(\mu=\frac{4}{3}\right)$$ is shown in figure. The apparent depth of the image of the bubble in plane mirror viewed by observer is.

COMEDK 2023 Morning Shift Physics - Ray Optics Question 25 English

COMEDK 2023 Morning Shift
25

A fish in water (refractive index $$n$$ ) looks at a bird vertically above in the air. If $$y$$ is the height of the bird and $$x$$ is the depth of the fish from the surface, then the distance of the bird as estimated by the fish is

COMEDK 2023 Morning Shift
26

The critical angle of a medium having the refractive index $$\sqrt2$$ is :

COMEDK 2023 Evening Shift
27

When angle of incidence on one face of the equilateral glass prism is $$3 / 4^{\text {th }}$$ of the angle of prism, the ray of light undergoes minimum deviation. If the velocity of light in vacuum is '$$c$$' then the velocity of light in the glass is :

COMEDK 2023 Evening Shift
28

A person has a normal near point $$25 \mathrm{~cm}$$. What is the magnifying power of the simple microscope he used, if the focal length of the convex lens used is $$10 \mathrm{~cm}$$ and the final image is formed at the least distance of distinct vision?

COMEDK 2023 Evening Shift
29

A lens of power $$+1 \mathrm{D}$$ is made in contact with another lens of power $$-2 \mathrm{D}$$ the combination will then act as a:

COMEDK 2023 Evening Shift
30

What will be change in wave length, if a light of wave length $$600 \mathrm{~nm}$$ travels from air enters a medium of refractive index 1.5 and continues its journey through that medium?

COMEDK 2023 Evening Shift
31

A point object is placed on the optic axis of a convex lens of focal length $$f$$ at a distance of $$2f$$ to the left of it. The diameter of the lens is $$d$$. An eye is placed at a distance of $$3f$$ to the right of the lens and a distance $$h$$ below the optic axis. The maximum value of $$h$$ to see the image is

COMEDK 2022
32

A plane glass mirror of thickness 3 cm of material of $$\mu=\frac{3}{2}$$ is silvered on the black surface. When a point object is placed 9 cm from the front surface of the mirror, then the position of the brightest image from the front surface is

COMEDK 2022
33

Two converging lenses of focal length 20 cm and 40 cm are placed in contact. The effective power of the combination is

COMEDK 2021
34

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

COMEDK 2021
35

A convex lens is made of 3 layers of glass of 3 different materials as in the figure.

COMEDK 2020 Physics - Ray Optics Question 29 English

A point object is placed on its axis. The number of images of the object are

COMEDK 2020
36

A ray of light suffers minimum deviation in equilateral prism P. Additional prisms Q and R of identical shape and of same material as that of P are now combined as shown in figure. The ray will now suffer

COMEDK 2020 Physics - Ray Optics Question 28 English

COMEDK 2020
EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12