Advertisements
Advertisements
Question
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.
Advertisements
Solution
For total internal reflection to happen at AC face, `sin theta >= mu_"water"/mu_"prism" = "4/3"/"3/2" = 8/9 = 0.89` where, θ is angle of incidence.
Now from the figure, we can see that angle of incidence will be 60 degrees.
So `sin 60 = sqrt3/2 = 0.866` which is less than 0.89
So total internal reflection will not take place at the face AC
APPEARS IN
RELATED QUESTIONS
State the relation between the critical angle and the absolute refractive index of 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.
Plot a graph between
Sine of angle of incidence versus sine of angle of refraction,
Why do diamonds sparkle?
Draw a diagram, properly labelled, to illustrate the use of a total reflecting prism (a right-angled isosceles prism) to turn a ray of light through 180°. Name an instrument in which this device is used.
Critical angle of light passing from glass to air is maximum for ____________.
What is the phenomenon used in optical fiber? Explain.
The phenomena involved in the reflection of radiowaves by ionosphere is similar to ______.
Find the value of θ in the given figure.
