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How does photon energy change as light wavelength increases?

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A horizontal gradient bar displays the visible light spectrum from violet to red, labeled with corresponding frequency in terahertz, wavelength in nanometers, and photon energy in electron volts. — light When white light is spread apart by a prism or a diffraction grating, the colours of the visible spectrum appear. The colours vary according to their wavelengths. Violet has the highest frequencies and shortest wavelengths, and red has the lowest frequencies and the longest wavelengths.

In physics, the energy of a photon is inversely proportional to its wavelength. This means that as the wavelength of light increases, the energy of the individual photons decreases.41

This relationship is defined by the equation $E = h ν$ , where $E$ is the energy, $h$ is Planck’s constant, and $ν$ is the frequency. Because frequency and wavelength are inversely related ( $λ = c / ν$ ), a longer wavelength corresponds to a lower frequency, which in turn results in lower photon energy. Conversely, shorter wavelengths are associated with higher frequencies and higher energy photons.2341