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Question
A glass slab is placed over a page on which the word VIBGYOR is printed with each letter in its corresponding colour.
- Will the image of all the letters be in the same place?
- If not, the state which letter will be raised to the maximum. Give a reason for your answer.
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Solution
- The image of all the letters of the word VIBGYOR in their corresponding colours will not be at the same place.
- The letter of violet colour (i.e. V) appears to be raised maximum, while the letter of red colour (i.e. R) appears to be raised minimum.
Since apparent depth = `"real depth"/"refractive index"` and the refractive index of glass is most for the violet light while least for the red light, therefore the apparent depth is least for violet and most for the red.
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