Advertisements
Advertisements
Question
Name the factors affecting the critical angle for the pair of media.
Advertisements
Solution
Factors affecting the critical angle are:
- Colour (or wavelength) of light: The refractive index of a transparent medium is most for violet light and least for red light; therefore, the critical angle for a pair of media is least for violet light and most for red light. Thus, the critical angle increases with increase in wavelength of light.
- Temperature: On increasing the temperature of the medium, its refractive index decreases, so the critical angle for that pair of media increases. Thus, the critical angle increases with increase in temperature
APPEARS IN
RELATED QUESTIONS
Which colour of light has a higher critical angle? Red light or green light.
Solve the previous problem if the paperweight is inverted at its place so that the spherical surface touches the paper.
Plot a graph between
Angle of incidence versus angle of reflection,
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.
How is the critical angle of a material related to its refractive index?
Choose the correct option.
Select the WRONG statement.
Answer the following question.
Define the critical angle of incidence and obtain an expression for it.
Which of the following statements about total internal reflection is true?
Write any two uses of total internal reflection.
- Assertion (A): Propagation of light through an optical fibre is due to total internal reflection taking place at the core-cladding interface.
- Reason (R): Refractive index of the material of the cladding of the optical fibre is greater than that of the core.
