Concept explainers
(a)
The expression of the integer
(a)
Answer to Problem 49CP
The expression of the integer
Explanation of Solution
Given info: The index reflection for film is
The condition of the destructive interference for minimum intensity is,
Here,
Rearrange the equation (1) to find the
The condition of constructive interference for the maximum intensity of fringes is,
Rearrange the equation (2) to find the
Since,
The wavelength of the maximum intensity is greater than the wavelength of the minimum intensity.
Substitute
Hence, the above equation exists for
Substitute
Substitute
Conclusion:
Therefore, the expression of the integer
(b)
The best thickness of the film.
(b)
Answer to Problem 49CP
The best thickness of the film is
Explanation of Solution
Given info: The index reflection for film is
Thus, the expression of the integer order of fringe
Substitute
The condition of the destructive interference for minimum intensity is,
Substitute
The condition of constructive interference for the maximum intensity of fringes is,
Substitute
Substitute
The average of the thickness at minimum intensity and thickness of the maximum intensity is,
The average of the thickness at minimum intensity and thickness of the maximum intensity represents the best thickness of film.
Conclusion:
Therefore, the best thickness of the film is
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Chapter 36 Solutions
Physics for Scientists and Engineers with Modern Physics
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