The difference in the number of waves when yellow light propagates through air and vacuum columns of the same thickness is one. The thickness of the air column is ___________ mm. [Refractive index of air = 1.0003, wavelength of yellow light in vacuum = 6000 $\mathop A\limits^o$]
Answer (integer)
2
Solution
Thickness t = n$\lambda$<br><br>So, n $\lambda$<sub>vac</sub> = (n + 1) $\lambda$<sub>air</sub><br><br>n $\lambda$ = (n + 1) ${\lambda \over {{\mu _{air}}}}$<br><br>n = ${1 \over {{\mu _{air}} - 1}} = {{{{10}^4}} \over 3}$<br><br>t = n$\lambda$<br><br>$= {{{{10}^4}} \over 3} \times 6000\mathop A\limits^o$<br><br>= 2 mm
About this question
Subject: Physics · Chapter: Optics · Topic: Reflection and Mirrors
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