Electromagnetic spectrum:
A diagram that illustrates all the varieties of electromagnetic waves based on their relative frequency/wavelengths.  Our eyes observe only a small amount of this spectrum.

Speed of light:
In a vacuum 3x10⁸ m/s.  It was first calculated by Olaus Roemer.  Albert Michelson also performed an experiment to refine the value.

Principle of superposition:
When two or more waves occupy the same region of space simultaneously, the resulting wave disturbance is the sum of separate waves.

Constructive interference:
Two or more waves superimposing to create a resulting wave that has a larger amplitude.

Destructive interference:
Two or more waves superimposing to create a resulting wave that has a smaller amplitude.

Thin film interference:
The principle that creates colors on thin layers of transparent substances.  The light reflecting off the interior of the substance interferes with light reflecting off the exterior.

Coherent light:
Light wave that are all in phase or in step.

Monochromatic light:
Light waves that possess the same frequency, color, or wavelength.

Diffraction:
The bending of waves around obstacles, corners, or openings.

Polarized light:
Light where the electric field fluctuates in only one direction.

The electromagnetic spectrum describes the wide variety of light observed.  Light can behave as a particle, or a wave.  In this tutorial topic, the wave nature of light is emphasized.  Young’s double slit experiment shows how light can constructively and destructively interfere.  The alternating bright and dark fringes are explained mathematically.  Diffraction grating of multiple slits also exhibit similar behavior.  Another wave feature of light is polarization.  Because light is a transverse wave, it can be polarized to vibrate in only one direction.  This can be accomplished with polarizing filters.  Malus’ law describes the reduced light intensity caused by a pair of polarizing filters.

Specific Tutorial Features:

• Diagram showing interference during Young’s double slit experiment.
  
• Examples with step by step assistance to solve problems.

Series Features:

• Concept map showing inter-connections of new concepts in this tutorial and those previously introduced.
  
• Definition slides introduce terms as they are needed.
  
• Visual representation of concepts
  
• Animated examples—worked out step by step
  
• A concise summary is given at the conclusion of the tutorial.

Electromagnetic spectrum

• Electromagnetic waves
  
• Speed of light calculations

Principle of superposition

• Constructive interference
  
• Destructive interference

Coherent and monochromatic light

Young’s double slit experiment

• Maxima positions
  
• Minima positions
  
• Formulas
  
• Examples

Diffraction gratings

• Formula
  
• Examples

Polarization

• Unpolarized light
  
• Filters
  
• Malus’ law