The disturbance (not the particles of the medium) travels.
The direction of the wave compared to the direction of the motion of the vibrating particles determines the type of wave.
Two wave types:
1. Transverse Waves: vibrate at right angles to the direction of the wave
2. Longitudinal Waves: vibrate back and forth, parallel to the direction the wave travels
Properties of Light Waves
In a transverse wave:
High point of a wave --- crests
Low point of the wave --- troughs
Wave length --- distance between two successive crests or troughs
Frequency --- the number of vibrations per second the wave makes
Long wavelengths = low frequencies
Short wavelengths = high frequencies
Velocity --- wavelength x frequency
Visible Light --- six basic colors (when all colors are seen together appears white)
Basic Colors --- red, orange, yellow, green, blue, and violet
Each color has a characteristic wavelength and frequency.
Red --- longest wavelength and the lowest frequency
Violet --- shortest wavelength and the highest frequency
Polarization of Light
Unpolarized --- vibrating in all directions
Polarized --- vibrating in a single path
Polarizer --- the crystal that produces polarized light
Polaroid --- artificial material that acts as a polarizer
Uses of polarized light:
Polarizing lenses --- reduce glare
Used by engineers to locate point of stress in automobiles and machinery
Identify different types of crystals.
Presented By: BW