Model Answers - 5c Wave Particle Duality

Question 1

Define intensity of light in the wave model of light

Answer 1

Intensity is power/area
Intensity is proportional to the amplitude of the wave squared - this is related to the energy of the wave

Question 2

define photon

Answer 2

discrete packet of electromagnetic energy

Question 3

describe what is meant by the wave particle duality of light

Answer 3

• light exhibits wave behaviour (diffraction, interference, superposition, polarisation)
• light exhibits particle behaviour (absorption and emission line spectra, photoelectric effect)
• so light exhibits both wave and particle behaviour: it exhibits wave particle duality

Question 4

define work function

Answer 4

minimum energy required for electron to be released from the surface of a metal