Introduction
 

Wave–particle duality is one of the fundamental ideas of quantum physics. It describes how electromagnetic radiation and matter can display both wave-like and particle-like behaviour, depending on the experiment being performed. This concept challenged classical Physics and led to the development of quantum theory.
 

In this topic, students learn about the evidence supporting wave–particle duality, including the behaviour of photons and electrons. Understanding this topic is essential for explaining phenomena such as diffraction, the photoelectric effect and the behaviour of matter at the atomic scale.
 

AQA A Level Physics Specification: 3.2.2.4 Wave–Particle Duality
 

What You Need to Know
 

• Describe the wave model and particle model of electromagnetic radiation.

• Explain why neither the wave model nor the particle model alone can explain all experimental observations.

• Understand that electromagnetic radiation exhibits both wave-like and particle-like properties.

• Describe how electrons can also display wave-like behaviour.

• Explain the significance of electron diffraction as evidence for the wave nature of matter.

• Understand the concept of wave–particle duality and its importance in quantum physics.

• Apply the de Broglie equation when calculating the wavelength of particles.
   

Downloadable Topic Pack
 

Wave–Particle Duality Past Exam Question & Answer Pack
 

Related Topics
 

• The Photoelectric Effect

• Energy Levels and Photon Emission

• Electromagnetic Radiation

• Collisions of Electrons with Atoms

• Atomic Structure and Specific Charge