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प्रश्न
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.

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उत्तर
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
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संबंधित प्रश्न
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2) State the condition so that internal reflection occurs in the above diagram.
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What do you understand by the deviation produced by a prism? Why is it caused?
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 –
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Plot a graph between
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Name the factors affecting the critical angle for the pair of media.
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