3.4 Electric and Magnetic Components of Light

Learning Objectives

Differentiate between the electric and magnetic components of light.

Prior Knowledge and Skills


Key Terms

  • Electric Field Vector
  • Magnetic Field Vector

Guided Inquiry



Figure 3.4.1. The electric and magnetic field vectors of an electromagnetic wave.  Figure 24.7 from https://cnx.org/contents/Ax2o07Ul@14.48:R_XAX-aM@9/24-2-Production-of-Electromagnetic-Waves.

3.4.1 What is the spatial relationship between the electric vector and the magnetic vector of light?  Be as specific as possible.

3.4.2 What is the symbol for the electric field vector?  For the magnetic field vector?

Concept Check 3.4.1.

Given that infrared and Raman spectroscopies will measure vibrations of chemical bonds in materials, and those bonds are produced from sharing or capturing electrons, do you think that we will use the electric vector or magnetic field vector interactions to understand infrared and Raman spectroscopy? Why?

What about NMR (nuclear magnetic resonance), which measures changes in the magnetic moment of odd-numbered atomic nuclei?


Want to learn more about electric and magnetic fields? See the OpenStax physics book referenced below.


Crash Chemistry Academy (September 3, 2017) Light, photons, and oscillating electromagnetic fields explained. https://youtu.be/YSgk78ToKrs.

Figure from: OpenStax, College Physics. OpenStax CNX. Mar 4, 2019 Production of Electromagnetic Waves. https://cnx.org/contents/Ax2o07Ul@14.48:R_XAX-aM@9/24-2-Production-of-Electromagnetic-Waves

OpenStax, College Physics. OpenStax CNX. Mar 4, 2019 http://cnx.org/contents/031da8d3-b525-429c-80cf-6c8ed997733a@14.48.