The wavelength of a photon can be calculated using the equation:
λ = hc/E
where λ is the wavelength, h is Planck's constant (approximately 6.626 x 10^-34 joule-seconds), c is the speed of light (approximately 3 x 10^8 meters per second), and E is the energy of the photon.
To find the wavelength of a 3 eV photon, we need to convert the energy from electron volts (eV) to joules (J). The conversion factor is 1 eV = 1.602 x 10^-19 J.
Therefore, the energy of a 3 eV photon is:
E = 3 eV x (1.602 x 10^-19 J/eV) = 4.806 x 10^-19 J
Substituting this value into the equation, we have:
λ = (6.626 x 10^-34 J·s × 3 x 10^8 m/s) / (4.806 x 10^-19 J) ≈ 4.121 x 10^-7 meters
So, the wavelength of a 3 eV photon is approximately 4.121 x 10^-7 meters or 412.1 nanometers.