Light is a wave and a particle?

[Rogelio Bazan 1D]

Dr. Lavelle in lecture began to explain in class about the classical behavior of a light wave, but what got me confused was toward the end of the lecture we began to talk about light as if it was a particle and not a wave. Why is this? Does it have anything to do with what we discussed, the Photoelectric effect?

Thanks,
Roger Bazan

[AnthonyDis1A]

Light can be both a wave and a stream of particles (photons). It travels as a wave, but when participating in chemical reactions (i.e. being absorbed or emitted by elements), transfer energy in distinct quantities/particles. The photoelectric effect is one of those example chemical reactions.

[Chem_Mod]

Light can act both as a wave and a particle. This is the phenomenon of wave-particle duality. The light shown via diffraction was thought of as waves in the classical thinking, but quantum mechanics and experiments such as the photoelectric effect have shown that light can also act like a particle which transfers its quanta of energy. We accept this dual behavior because of the experimental observations we made, not necessarily due to having a perfect explanation for it.

[Christina Inchuachan 1C]

Light is both a wave and a particle. Light has wave-like characteristics such as diffraction, reflection, and refraction. When UV light hits a metal surface, it causes an emission of electrons, called the photoelectric effect. The photoelectric effect supports that light is also a stream of particles.

[Cameron Smith 1I]

Would there be any instance in which light acts as a wave but not a particle?

[Chem_Mod]

All the statement is saying is that light can behave like a wave and/or also behave like a particle. So, there are situations where describing wave-like is more applicable (diffraction) or describing particle-like is more applicable (photoelectric effect).