Q 12-10-106JEE MainJEE Main 2021 (27 Jul, Shift 2)Easy
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 $= 1.0003$, the wavelength of yellow light in vacuum $= 6000$ Å]
Numerical value type. Enter your answer.
Answer: 2
Number of waves in thickness $t$: $\dfrac{t}{\lambda/\mu}$ in air and $\dfrac t\lambda$ in vacuum.
$$\frac{t(\mu - 1)}{\lambda} = 1 \Rightarrow t = \frac{6\times10^{-7}}{0.0003} = 2\times10^{-3}\ \text{m} = 2\ \text{mm}$$
Solution by Sreeraj P, M.Sc Physics