Chapter 12 Flashcards
amplitude
the height of a wave, measured from the center line of a wave to the top of a peak.
crystallography
the study of crystal structures by means of X-Ray diffraction.
diffraction
when waves encounter corners or obstructions and bend and spread out a s a result.
Doppler effect
the change of pitch perceived when the pitch is produced by a moving object and the object passes by the observer. the pitch is higher than normal as the moving object approaches because the motion compresses the wave length of the sound waves, and lower than normal after the object passes because the motion stretches the out the wavelength of the sound waves.
echolocation
the process used by bats, dolphins, and other some animals to navigate and hunt by means of emitting sounds and interpreting the echoes that come back.
frequency
an oscillating system, the number of cycles completed per second.
incident
a term that describes a ray or wave as it approaches the boundary of a new medium, where it reflects and/or refracts.
longitudinal wave
a wave with the characteristic that the oscillation producing the wave is moving parallel to the direction in which the wave propagates.
mechanical wave
any wave requiring a medium in which to propagate; all waves except electromagnetic waves.
medium
matter of some kind through which the energy of mechanical waves can propagate.
normal line
a line perpendicular to the boundary between two media, used as a reference for measuring angles involved in wave reflection and referaction.
oscillation
continuous, periodic moment back and forth or up and down.
period
the length of time required for an osculating system to complete one full cycle of its oscillation.
reflection
when a wave bounces of the boundary between two media, obeying the law of reflection in the process.
refraction
when a wave passes through a boundary separating two media, changing velocity and direction in the process.
