## Explaining particle-like nature of electromagnetic radiation on HW 1.21 [ENDORSED]

$c=\lambda v$

Maya_McNealis1B
Posts: 9
Joined: Wed Sep 21, 2016 2:59 pm

### Explaining particle-like nature of electromagnetic radiation on HW 1.21

HW Question 1.21 asks you to choose which phenomena from a list of observations best supports the idea that electromagnetic radiation has the properties of particles. The options are a) black body radiation, b) electron diffraction, c) atomic spectra and d) the photoelectric effect.

I understand that the correct answer is D, but I'm wondering if my explanation is the correct justification for the answer.

Black body radiation demonstrates how the structure of atoms & molecules restrict the types of frequencies they emit, so A is not the answer.

Electron diffraction explains how electrons act as waves, so B is not the answer.

Atomic spectra describe the specific energy levels that electrons can have, so C is not the answer.

D is the answer because the photoelectric effect demonstrates how light, acting as "packets" or particles of energy called photons, can excite electrons in a 1:1 ratio, thereby illustrating the particle-like nature of EMR.

Scott_Anderson_3J
Posts: 11
Joined: Wed Sep 21, 2016 2:56 pm

### Re: Explaining particle-like nature of electromagnetic radiation on HW 1.21  [ENDORSED]

Your answer seems to be the right explanation. The solutions manual says, "Einstein proposed that EMR consists of particles (or packets) of energy called photons, each photon having a fixed energy equal to hv. Your answer that EMR contains particles and that light consists of packets called photons is in line with the solutions manual.