What is wave-particle duality?
1 Answer
Jun 22, 2014
Wave-particle duality means that light behaves as a wave in some experiments. In other experiments, light behaves as a particle.
In 1801, Thomas Young shone light between two parallel slits. The light waves interfered with each other and formed a pattern of light and dark bands.

If the light had consisted of small particles, they would have passed straight through the slits and formed two parallel lines.
![]()
In 1905, Albert Einstein showed that a beam of light could eject electrons from a metal. He found that photons with a frequency over a certain level would have sufficient energy to eject an electron. The light was behaving as a stream of particles, like machine gun bullets.

Hope this helps.
