In the photoelectric effect, what does the energy of photons depend on?

In the context of the photoelectric effect, the energy of photons is fundamentally related to both the wavelength and frequency of the light. The relationship is defined by the equation ( E = hf ) or ( E = \frac{hc}{\lambda} ), where ( E ) is the energy of a photon, ( h ) is Planck's constant, ( f ) is the frequency of the light, ( c ) is the speed of light, and ( \lambda ) is the wavelength.

As frequency increases, the energy of the photons also increases, which aligns with the quantum theory of light. Conversely, longer wavelengths correspond to lower frequencies and, thus, lower energies. This fundamental dependence on wavelength and frequency illustrates why, for instance, ultraviolet light can cause the ejection of electrons from a material while visible light may not possess enough energy to do so.

In relation to the other options, the type of metal surface does influence the threshold frequency needed for electron ejection, but it does not affect the intrinsic energy of the photons themselves. The temperature of the environment can affect experimental outcomes but does not change photon energy directly, nor does the intensity of the light, which relates to the number of photons rather than