Answer:
(a) λ = 4136 nm → infrared
(b) λ = 413.6 nm → visible light
(c) λ = 41.36 nm → ultraviolet
Explanation:
The wavelength of infrared is on the range of 700 nm to 1000000 nm
The wavelength of visible light is between 400 nm and 700 nm
The wavelength of ultraviolet ray on the range of 10 nm to 400 nm
The wavelength of photon is given by;
E = hf
f is the frequency of the wave = c / λ
[tex]E = h\frac{c}{\lambda}\\\\ \lambda = \frac{hc}{E}[/tex]
Where;
c is the speed of light = 3 x 10⁸ m/s
h is Planck's constant = 6.626 x 10⁻³⁴ J/s
(a) 0.3 eV = 0.3 x 1.602 x 10⁻¹⁹ J
[tex]\lambda = \frac{(6.626 * 10^{-34})(3*10^8)}{(0.3)*(1.602*10^{-19})}\\\\\lambda = 4.136 *10^{-6} \ m[/tex]
λ = 4136 x 10⁻⁹ m
λ = 4136 nm → infrared
(b) 3.0 eV
[tex]\lambda = \frac{(6.626 * 10^{-34})(3*10^8)}{(3)*(1.602*10^{-19})}\\\\\lambda = 4.136 *10^{-7} \ m[/tex]
λ = 413.6 x 10⁻⁹ m
λ = 413.6 nm →visible light
(c) 30 eV
[tex]\lambda = \frac{(6.626 * 10^{-34})(3*10^8)}{(30)*(1.602*10^{-19})}\\\\\lambda = 4.136 *10^{-8} \ m[/tex]
λ = 41.36 x 10⁻⁹ m
λ = 41.36 nm →ultraviolet
