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प्रश्न
In the following figure, show two rays A and B travelling from water to air. If the critical angle for water- air surface is 48°, complete the ray diagram showing the refracted rays for each. State conditions when the ray will suffer total internal reflection.
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उत्तर
The necessary conditions for total internal reflection to occur are
- Light must travel from a denser medium to a rarer medium.
- The angle of incidence must be greater than the critical angle.
In this case, the angle of incidence. ∠ i > 48°
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संबंधित प्रश्न
A ray of light travels from water to air as shown in the diagram given below :
1) Copy the diagram and complete the path of the way. Given the critical angle for water is 48°.
2) State the condition so that internal reflection occurs in the above diagram.
Which colour of light has a higher critical angle? Red light or green light.
A light ray does not bend at the boundary in passing from one medium to the other medium if the angle of incident is ______.
Write the relation between the refractive index and critical angle for a given pair of optical media?
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 Numerical example.
A monochromatic ray of light is incident at 37° on an equilateral prism of refractive index 3/2. Determine angle of emergence and angle of deviation. If angle of prism is adjustable, what should its value be for emergent rays to be just possible for the same angle of incidence?
A bundle of glass threads, each of which is capable of transmitting messages using light waves is called ______.
The critical angle is defined as the angle of incidence at which the total internal reflection starts to occur.
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State the condition under which total internal reflection occurs. Give the mathematical expression for total internal reflection.
