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प्रश्न
Small air bubbles rising up a fish tank appear silvery when viewed from some particular angle is due to the ______.
पर्याय
reflection
refraction
dispersion
total internal reflection
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उत्तर
Small air bubbles rising up a fish tank appear silvery when viewed from some particular angle is due to the total internal reflection.
Explanation:
If the angle of incidence is larger than the critical angle, a light beam that is travelling from an optically denser to a rarer medium reflects back into the denser medium.
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संबंधित प्रश्न
The diagram below shows a point source P inside a water container. Four rays A, B, C, D starting from the source P are shown up to the water surface
1) Show in the diagram the path of these rays after striking the water surface.
The Critical Angle for the water-air surface is 48°.
2) Name the phenomenon which the rays B and D exhibit.
Total internal reflection occurs only when a ray of light passes from a ______ medium to a ______ medium.
Write the necessary conditions for the phenomenon of total internal reflection to
occur ?
Swarali has got the following observations while doing an experiment. Answer her questions with the help of observations.
Swarali observed that the light bent away from the normal, while travelling from dense medium to rarer medium. When Swarali increased the values of angle of incidence (i), the values of angle of refraction (r) went on increasing. But at a certain angle of incidence, the light rays returned into the dense medium.
So, Swarali has some questions. Answer them –
a) Name this certain value of ‘i ’. What is the value of ‘r’ at that time ?
b) Name this process of returning of light in dense medium. Explain the process.
Solve the previous problem if the paperweight is inverted at its place so that the spherical surface touches the paper.
A ray of light is incident as a normal ray on the surface of separation of two different mediums. What is the value of the angle of incidence in this case?
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
Describe the construction and working of an optical fibre.
What are the conditions to achieve total internal reflection?
A rectangular block of glass ABCD has a refractive index 1.6. A pin is placed midway on the face AB (Figure). When observed from the face AD, the pin shall ______.
- appear to be near A.
- appear to be near D.
- appear to be at the centre of AD.
- not be seen at all.
