Advertisements
Advertisements
प्रश्न
A spherical marble, of refractive index 1.5 and curvature 1.5 cm, contains a tiny air bubble at its centre. Where will it appear when seen from outside?
विकल्प
1 cm inside
at the centre
`5/3` cm inside
2 cm inside
Advertisements
उत्तर
`bb(5/3)` cm inside
Explanation:
The refractive index of the marble is 1.5.
One can see the image formed due to the reflection in the spheres.
In order to determine the distance where the image will form, use the lens maker formula.
Hence, `mu_1/v - mu_2/u = (mu_2 - mu_1)/"R"`
Where, refractive index of air = 1, refractive index of glass = 1.5, Radius of the curvature = 1.5 cm
Substituting the values, we get,
`therefore 1/v - 1.5/0.75 = (1 - 1.5)/1.5`
`therefore 1/v - 2 = - 0.5/1.5`
`therefore 1/v - 2 = - 1/3`
`therefore 1/v = - 1/3 + 2`
`therefore 1/v = (- 1 + 6)/3`
`therefore 1/v = 5/3`
Therefore, the tiny bubble will be seen 5/3 cm inside when we see it from the outside.
APPEARS IN
संबंधित प्रश्न
You are given prisms made of crown glass and flint glass with a wide variety of angles. Suggest a combination of prisms which will
(a) deviate a pencil of white light without much dispersion,
(b) disperse (and displace) a pencil of white light without much deviation.
The figure shows a ray of light falling normally on the face AB of an equilateral glass prism having refractive index`3/2`, placed in water of refractive index `4/3`.Will this ray suffer total internal reflection on striking the face AC? Justify your answer.
State the relation between the critical angle and the absolute refractive index of a medium.
Angle of deviation is the angle which the ______ ray makes with the direction of ______ray.
State two conditions necessary for total internal reflection to occur.
Total internal reflection occurs only when a ray of light passes from a ______ medium to a ______ medium.
The observation made by Swarali while doing the experiment is given below. Based on these write answers to the questions:
Swarali found that the light ray travelling from the denser medium to rarer medium goes away from the normal. If the angle of incidence (i) is raised by Swarali, the angle of refraction (r) went on increasing. However, after certain value of the angle of incidence the light ray is seen to return back into the denser medium.
Questions:
- What is the specific value of∠i called?
- What is the process of reflection of incident rays into denser medium called?
- Draw the diagrams of three observations made by Swarali.
(i) Define critical angle.
(ii) State one important factor which affects the critical angle of a given medium.
Make the correct choices for each of the following :
Total Internal reflection takes place when
(where ∠i = angle of incidence, ∠r = angle of refraction, ∠C = critical angle)
Express the refractive index μ of a medium in terms of the angle of incidence i in air and the angle of refraction r in a denser medium.
Images formed by totally reflecting prisms are brighter than the image formed by ordinary reflected light, why?
A ray of light incident at an angle of incidence ‘i’ passes through an equilateral glass prism such that the refracted ray inside the prism is parallel to its base and emerges from the prism at an angle of emergence ‘e’.
What can you say about the value of the angle of deviation in such a situation?
Complete the following diagram to show the path of the ray of a single colour in the diagram as if enters in and emerges out of the prism. Mark the angles wherever necessary. (Critical angle for glass = 42°).
Choose the correct option.
Consider the following phenomena/ applications: P) Mirage, Q) rainbow, R) Optical fibre and S) glittering of a diamond. Total internal reflection is involved in
Answer the following question.
What are the advantages of optical fibre communication over electronic communication?
Answer the following question.
Why is prism binoculars preferred over traditional binoculars? Describe its working in brief.
A green light is incident from the water to the air-water interface at the critical angle (C). Select the correct statement.
Total internal reflection can take place only if light is travelling from ______.
Optical fibre communication uses the principle of ______.
A particle is projected such that the horizontal range and vertical height are equal. Then the angle of projection is :
Which of the following statements about total internal reflection is true?
What is the phenomenon used in optical fiber? Explain.
A green light is incident from the water to the air-water interface at the critical angle (θ). Select the correct statement.
A jar of height h is filled with a transparent liquid of refractive index µ (Figure). At the centre of the jar on the bottom surface is a dot. Find the minimum diameter of a disc, such that when placed on the top surface symmetrically about the centre, the dot is invisible.
A given ray of light suffers minimum deviation in an equilateral prism P. Additional prism Q and R of identical shape and of the same material as P are now added as shown in the figure. The ray will now suffer ______.
Small air bubbles rising up a fish tank appear silvery when viewed from some particular angle is due to the ______.
