Question

Orange light of wavelength 0.61 µ m in air enters a block of glass with εr = 1.44. What color would it appear to a sensor embedded in the glass? The wavelength ranges of colors are violet (0.39 to 0.45 µ m), blue (0.45 to 0.49 µ m), green (0.49 to 0.58 µ m), yellow (0.58 to 0.60 µ m), orange (0.60 to 0.62 µ m), and red (0.62 to 0.78 µ m)

Answer 1

`0.5083\ \mu m`

Step-by-step explanation:

`\lambda_0` = Actual wavelength =
`0.61\ \mu m`

`\varepsilon_r` = Relative permittivity = 1.44

The observed wavelength in the glass is given by

`\lambda=(\lambda_0)/(√(\varepsilon_r))\\\Rightarrow \lambda=(0.61)/(√(1.44))\\\Rightarrow \lambda=0.5083\ \mu m`

The wavelength lies in the range of green light.

Hence, the observed color of light is
`0.5083\ \mu m`