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Chinmayi
Subject: Physics
, asked on 28/4/18
Kindly answer.
Q.47. The critical angle for a beam of light passing from a diamond into the air is 24.4
°
. This means that any light rays that strike the surface interface between the diamond and the air with an angle less than
24.4
°
are
(A) completely reflected.
(B) partially reflected and partially refracted.
(C) completely absorbed.
(D) partially absorbed and partially transmitted.
(E) completely transmitted.
Answer
1
Sandra Saju
Subject: Physics
, asked on 28/4/18
The focal length of a convex lens is f. An object is placed at a distance x from its first focal point. The ratio of the size of the real image to that of the object is (i) f/x2. (ii) x2/f. (iii) f/x. (iv) x/f
Answer
1
Charu
Subject: Physics
, asked on 27/4/18
Question 9
9.
If a thin film of thickness 2 cm and refractive index 1.5 is placed in the path of light coming from a source S, then in length of optical path is
(1) 1 cm (2) 2 cm
(3) 3 cm (4) 4 cm
Answer
1
Jeneeta Eliza John
Subject: Physics
, asked on 24/4/18
Please Explain the following....Please do not send any links. I am unable to understand that answer
Q.33. Two thin similar convex glass pieces are joined together front to front with its rear portion silvered such that a sharp image is formed 20 cm from the mirror. When the air between the glass pieces is replaced by water (
m
W
= 4/3), then the image formed from the mirror is at a distance of
(1) 8 cm
(2) 10 cm
(3) 6 cm
(4) 12 cm
Answer
1
Aparna Sahu
Subject: Physics
, asked on 24/4/18
Solve this:
Q.43. The least distance of vision of a longsighted person is 60 cm. By using a spectacle lens, this distance is reduced to 12 cm. The power of the lens is
(a) + 5.0 D
(b) + (20/3) D
(c) - (10/3) D
(d) + 2.0 D
Answer
1
Jeneeta Eliza John
Subject: Physics
, asked on 24/4/18
Focal length of objective eye piece and inverting lens of a terrestrial telescope are 20cm, 10cm and 5 cm resp. Length of the tube containing these lenses at normal adjustment is? Ans is 50cm. Please explain how
Answer
1
Tarun Krishnan
Subject: Physics
, asked on 21/4/18
Q 31
. A tank contains a slab of glass 8 cm thick and of refractive index 1.6. Above this, is a depth of 4.5 cm of an oil and upon this a layer of water 6 cm thick and of refractive index 4/3. To an observer, looking down from above, a mark at the bottom appears to be raised upto position 6 cm from the bottom of the slab. The refractive index of oil is
a) 0.8
b) 1.2
c) 1.5
d) 1.8
Answer
1
Tarun Krishnan
Subject: Physics
, asked on 21/4/18
Q. Calculate the R.I. of the medium for which the critical angle is 42
°
.
Q. Mention the conditions for total internal reflection of a light ray.
Q. Mention any two applications Of total internal reflection.
Any two applications
Q. Write any two advantages of optical fibres over metallic cable in
communication. Any two advantages
Q. A tank contains a slab or glass 8 cm thick and of refractive index 1.6. Above this, is a depth of 4.5 cm Of an oil and upon this a layer of water 6 cm thick and of refractive index 4/3. To an observer, looking down from above, a mark at the bottom appears to be raised
upto position 6 cm from the bottom of the slab. The refractive index of oil is
a) 0.8
b) 1.2
c) 1.5
d) 1.8
Answer
1
Tarun Krishnan
Subject: Physics
, asked on 21/4/18
Q. Calculate the R.I. of the medium for which the critical angle is 42
°
.
°
Q. Mention the conditions for total internal reflection of a light ray.
Q. Mention any two applications Of total internal reflection.
Any two applications
Q. Write any two advantages of optical fibres over metallic cable in
communication. Any two advantages
Q. A tank contains a slab or glass 8 cm thick and of refractive index 1.6. Above this, is a depth of 4.5 cm Of an oil and upon this a layer of water 6 cm thick and of refractive index 4/3. To an observer, looking down from above, a mark at the bottom appears to be raised
upto position 6 cm from the bottom of the slab. The refractive index of oil is
a) 0.8
b) 1.2
c) 1.5
d) 1.8
Answer
1
Tarun Krishnan
Subject: Physics
, asked on 21/4/18
Q 30.
Write any two advantages of optical fibres over metallic cable in communication.
Answer
2
Tarun Krishnan
Subject: Physics
, asked on 21/4/18
30. Write any two advantages of optical fibres over metallic cable in communication.
Answer
1
Tarun Krishnan
Subject: Physics
, asked on 21/4/18
Q
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.
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Answer
1
Tarun Krishnan
Subject: Physics
, asked on 21/4/18
Q 3.
A coin at the bottom Of a beaker 0.1 m deep appears to be raised by 0.03 m when the beaker is filled with a liquid upto its brim. Calculate the R.I. of the liquids.
Answer
1
Mohan
Subject: Physics
, asked on 20/4/18
tricks to solve the ray optics problems in 30 sec
Answer
1
Prerna Varshney
Subject: Physics
, asked on 20/4/18
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What are you looking for?
Q.47. The critical angle for a beam of light passing from a diamond into the air is 24.4. This means that any light rays that strike the surface interface between the diamond and the air with an angle less than
24.4 are
(A) completely reflected.
(B) partially reflected and partially refracted.
(C) completely absorbed.
(D) partially absorbed and partially transmitted.
(E) completely transmitted.
9. If a thin film of thickness 2 cm and refractive index 1.5 is placed in the path of light coming from a source S, then in length of optical path is
(1) 1 cm (2) 2 cm
(3) 3 cm (4) 4 cm
Q.33. Two thin similar convex glass pieces are joined together front to front with its rear portion silvered such that a sharp image is formed 20 cm from the mirror. When the air between the glass pieces is replaced by water ( = 4/3), then the image formed from the mirror is at a distance of
(1) 8 cm
(2) 10 cm
(3) 6 cm
(4) 12 cm
Q.43. The least distance of vision of a longsighted person is 60 cm. By using a spectacle lens, this distance is reduced to 12 cm. The power of the lens is
(a) + 5.0 D
(b) + (20/3) D
(c) - (10/3) D
(d) + 2.0 D
a) 0.8
b) 1.2
c) 1.5
d) 1.8
Q. Mention the conditions for total internal reflection of a light ray.
Q. Mention any two applications Of total internal reflection.
Any two applications
Q. Write any two advantages of optical fibres over metallic cable in
communication. Any two advantages
Q. A tank contains a slab or glass 8 cm thick and of refractive index 1.6. Above this, is a depth of 4.5 cm Of an oil and upon this a layer of water 6 cm thick and of refractive index 4/3. To an observer, looking down from above, a mark at the bottom appears to be raised
upto position 6 cm from the bottom of the slab. The refractive index of oil is
a) 0.8
b) 1.2
c) 1.5
d) 1.8
Q. Mention the conditions for total internal reflection of a light ray.
Q. Mention any two applications Of total internal reflection. Any two applications
Q. Write any two advantages of optical fibres over metallic cable in communication. Any two advantages
Q. A tank contains a slab or glass 8 cm thick and of refractive index 1.6. Above this, is a depth of 4.5 cm Of an oil and upon this a layer of water 6 cm thick and of refractive index 4/3. To an observer, looking down from above, a mark at the bottom appears to be raised upto position 6 cm from the bottom of the slab. The refractive index of oil is
a) 0.8
b) 1.2
c) 1.5
d) 1.8