A particular photon has a wavelength of 450 nm and a second one has a wavelength of 580 nm.Which of the following statements about the energies of these two photons is TRUE?
A) All photons have the same energy, regardless of wavelength.
B) The 450-nm photon has the higher energy.
C) The 580-nm photon has the higher energy.
D) The photon from the higher-intensity light source has the higher energy (regardless of wavelength).

Question

Quizplus · Accepted Answer

The energy of a photon is inversely proportional to its wavelength, according to the equation E = hc/λ, where E is energy, λ is wavelength, h is Planck's constant, and c is the speed of light. Therefore, the photon with the shorter wavelength (450 nm) has the higher energy, while the photon with the longer wavelength (580 nm) has the lower energy. Choice A is incorrect because energy is dependent on wavelength. Choice C is incorrect because it is the opposite of the correct answer. Choice D is incorrect because intensity (brightness) does not affect the energy of a single photon, only the number of photons present.

A Particular Photon Has a Wavelength of 450 Nm and a Second