“Introduction to Light” Objectives

Students should be able to:

• Describe the debate Newton and Huygens about the nature of light
• Describe Huygens’ evidence for his views of the nature of light.
• Describe Raleigh scattering and where we observe it.
• Describe Newton’s evidence for his views of the nature of light.
• Describe the speed of light
• Memorize the speed of light in a vacuum as 3.00 x 108 m/s.
• Recite the time is takes for light to travel between the moon and the Earth and between our Sun and the Earth
• Describe the resolution of Newton and Huygens’ argument.
• Describe the “duality principle” of light.
• Compare wave types
• Longitudinal
• Translational
• Identify a waves amplitude, wavelength and period.
• Define the relationship between wave speed, frequency and wavelength.
• Mathematically define the energy of a photon of a given frequency (color.)
• Describe the colors of the visible spectrum from
• longest wavelength to shortest
• lowest frequency to highest frequency
• lowest energy to highest energy
• Sort the light/electromagnetic spectrum by AM/FM radio waves, microwaves, infrared, visible, ultraviolet, and x-rays.
• Conceptually explain how an LED works.
• Define “refraction” and “reflection”
• Sound refraction
• Light refraction by index and by gravity (Gravitational Lens)
• Define the index of refraction in terms of the speed of light in a vacuum and the average speed of light in a substance.
• Define Snell’s Law.
• Use Snell’s to find refraction angles.
• Define the conditions for the critical angle.
• Use Snell’s law to find the critical angle.
• Define polarization
• Describe polarization by filters and surfaces.
• Define Brewster’s Law of polarization