A back and forth motion that repeats itself is a
vibration.
The number of vibrations that occur in 1 s is called
frequency.
Frequency is measured in units of
hertz.
The maximum displacement from rest to the crest or from rest to the trough of a wave is called
amplitude.
A wave with motion perpendicular to the direction that the wave is moving is classified as a
transverse wave.
Your brain interprets a frequency as a sound with a certain
pitch.
Sound waves with frequencies greater than 20,000 Hz are
ultrasonic waves.
Generally, sounds travel faster in
solids.
Sounds travel faster in
warmer air.
The bending of a wave font between boundaries is
refraction.
A reflected sound that reaches the ear within 0.1 s after the original sound results in
reverberation.
The wave front of a refracted sound bends toward
cooler air.
Two in-phase sound waves with the same amplitude and frequency arrive at the same place at the same time, resulting in
a new sound wave with greater amplitude.
Two out-of-phase sound waves with the same amplitude and frequency arrive at the same place at the same time, resulting in
cancellation of the two sound waves
Two sound waves of equal amplitude with slightly different frequencies will result in
alternation of loudness of sound known as beats
Two sound waves of unequal amplitudes with different frequencies will result in
two separate sounds.
The energy of a sound wave is proportional to the rate of energy transferred to an area perpendicular to the waves, which is called the sound
intensity.
A decibel noise level of 40 would be most likely found
on a typical day in the library.
A resonant condition occurs when
an external force matches a natural frequency.
The fundamental frequency of a string is the
longest standing wave that can fit on the string.
The fundamental frequency on on a vibrating string is what part of a wavelength?
02-Jan
Higher resonant frequencies that occur at the same time as the fundamental frequency are called
overtones.
A moving source of sound or a moving observer experiences the apparent shift in frequency called
Doppler effect.
Does the Doppler effect occur when the observer is moving and the source of sound is stationary?
Yes, the effect is the same.
A rocket traveling a three times the speed of sound is traveling at
Mach 3.
A longitudinal mechanical wave causes particles of a material to move
back and forth in the same direction the wave is moving.
A transverse mechanical wave causes particles of a material to move
perpendicular to the direction the wave is moving.
Transverse mechanical waves will move only through
solids.
Longitudinal mechanical waves will move only through
all the above are correct.
A pulse jammed-together molecules that quickly moves away from a vibrating object
all of the above are correct.
The characteristic of a wave that is responsible for what you interpret as pitch is the wave
frequency.
Sound waves travel faster in
all the above are correct.
The difference between a echo and reverberation is
the time interval between the original sound and the reflected sound.
The fundamental frequency of a standing wave on a string has
two nodes and one antinode.
Sound interference is necessary to produce the phenomenon known as
beats.
An observer on the ground will hear a sonic boom from an airplane traveling faster than the speed of sound
after the plane has passed by.
What comment is true about the statement that "the human ear hears sounds originating from vibrating objects with a frequency between 20 and 20,000 Hz"?
Very few people hear this whole range, which decreases with age.
A sound wave that moves through the air is
pulses of increased and decreased air pressure.
During a track and field meet, the time difference between seeing the smoke from a starter's gun and hearing the bang would be less
on a warmer day.
What is changed by destructive interference of a sound wave?
Amplitude
An airplane pilot hears a slow beat from the two engines of his plane.
Increase the speed of the right engine.
Resonance occurs when an external force matches the
natural frequency.
The sound quality is different for the same-pitch note produced by two different musical instruments, but you are able to recognize the basic note because of the same
fundamental frequency.
What happens if the source of a sound is moving toward you at a high rate of speed?
You will hear a higher frequency, but people in the source will not.
What happens if you are moving at a high rate of speed toward some people standing next to a stationary source of sound? You will hear
a higher frequency than the people you are approaching will hear.