The answer depends on the wavelength of the photon.
Visible Light Spectrum
Humans can only see a small portion of the electromagnetic spectrum, known as visible light. This range of wavelengths is roughly between 380 nanometers (nm) and 750 nm.
- Photons with wavelengths within this range are visible to humans.
- Photons with wavelengths shorter than 380 nm fall into the ultraviolet (UV) range, which we cannot see.
- Photons with wavelengths longer than 750 nm fall into the infrared (IR) range, which we also cannot see.
Example
- A photon with a wavelength of 550 nm is green and visible to humans.
- A photon with a wavelength of 200 nm is ultraviolet and invisible to humans.
- A photon with a wavelength of 1000 nm is infrared and invisible to humans.
Therefore, to answer your question, we need to know the wavelength of the photon you are referring to.
