Question

El espectro visible en el aire está comprendido entre la longitud de onda 450 nm del color azul, Determina la velocidad de propagación.

Answer 1

v = 2,99913 10⁸ m / s

Step-by-step explanation:

The velocity of propagation of a wave is

v = λ f

in the case of an electromagnetic wave in a vacuum the speed that speed of light

v = c

When the wave reaches a material medium, it is transmitted through a resonant type process, whereby the molecules of the medium vibrate at the same frequency as the wave, as the speed of the wave decreases the only way that they remain the relationship is that the donut length changes in the material medium

λ = λ₀ / n

where n is the index of refraction of the material medium.

Therefore the expression is

v =
`(\lambda_o)/(n) f`

Let's look for the frequency of blue light in a vacuum

f =
`(c )/(\lambda_o)`

f =
`(3 \ 10^8)/(450 \ 10^(-9))`

f = 6.667 10¹⁴ Hz

the refractive index of air is tabulated

n = 1,00029

let's calculate

v =
`(450 \ 10^(-9) )/(1.00029) \ 6.667 \ 10^(14)`450 10-9 / 1,00029 6,667 1014

v = 2,99913 10⁸ m / s

we can see that the decrease in speed is very small