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PSYC 230 UIUC Exam #2 Questions and
Answers
Sound stimulus Ans: the periodic variations in air pressure
traveling out from the source
Sound waves Ans: the waves of pressure changes that occur in
the air as a function of the vibration of a source
Medium of sound Ans: A material (solid, liquid, or gas, or
combination of these) through which a wave travels. In water,
sound travels 4x faster than it does through air.
pure tones Ans: A sound wave in which changes in air pressure
follow a sine wave pattern.
amplitude Ans: the difference between the peak and the baseline
of a wave (height of wave).
loudness Ans: Perceptual experience of amplitude
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Loud sounds can be dangerous Ans: Prolonged contact to sounds
over 85 dB can eventually cause hearing loss. Sounds louder than
120 dB are painful. Sounds louder than 130 dB will generally result
in immediate and permanent hearing loss.
Frequency Ans: The number of cycles in a sound stimulus that
occur in 1 second
Pitch Ans: The subjective experience of frequency
what unit is used to measure sound amplitude? Ans: Hertz (Hz)
What is the hearing range of humans and how does it change with
age? Ans: 20-20,000 Hz. As people age, hearing in the highest
range dissipates. Lowest frequencies tend to remain stable with
age.
Outer ear Ans: Pinna, external auditory canal, tympanic
membrane (eardrum)
Pinna Ans: Collects sound and funnels it into the auditory canal
External auditory canal Ans: conducts sound to the tympanic
membrane, amplifies specific sound frequencies.
Tympanic membrane (eardrum) Ans: Thin elastic sheet.
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Middle ear Ans: Eustachian tube
Tensor tympani
Stapedius
Ossicles:
Malleus (hammer)
Incus (anvil)
Stapes (stirrup)
Eustachian tube Ans: Connects the middle ear with the pharynx.
Equalizes air pressure on either side of the eardrum
Tensor tympani and Stapedius Ans: Muscles attached to the
malleus and stapes
Incus (anvil) Ans: The middle bone which is connected to the
malleus and hammer, passes vibrations onto the stapes.
Ossicles Ans: 3 small bones in the middle ear that conduct sound
mechanically, goal is to amplify sounds
Malleus (hammer) Ans: Affixed to the tympanic membrane and
acts on the incus
© 2025 All rights reserved
PSYC 230 UIUC Exam #2 Questions and
Answers
Sound stimulus Ans: the periodic variations in air pressure
traveling out from the source
Sound waves Ans: the waves of pressure changes that occur in
the air as a function of the vibration of a source
Medium of sound Ans: A material (solid, liquid, or gas, or
combination of these) through which a wave travels. In water,
sound travels 4x faster than it does through air.
pure tones Ans: A sound wave in which changes in air pressure
follow a sine wave pattern.
amplitude Ans: the difference between the peak and the baseline
of a wave (height of wave).
loudness Ans: Perceptual experience of amplitude
© 2025 All rights reserved
, 2 | Page
Loud sounds can be dangerous Ans: Prolonged contact to sounds
over 85 dB can eventually cause hearing loss. Sounds louder than
120 dB are painful. Sounds louder than 130 dB will generally result
in immediate and permanent hearing loss.
Frequency Ans: The number of cycles in a sound stimulus that
occur in 1 second
Pitch Ans: The subjective experience of frequency
what unit is used to measure sound amplitude? Ans: Hertz (Hz)
What is the hearing range of humans and how does it change with
age? Ans: 20-20,000 Hz. As people age, hearing in the highest
range dissipates. Lowest frequencies tend to remain stable with
age.
Outer ear Ans: Pinna, external auditory canal, tympanic
membrane (eardrum)
Pinna Ans: Collects sound and funnels it into the auditory canal
External auditory canal Ans: conducts sound to the tympanic
membrane, amplifies specific sound frequencies.
Tympanic membrane (eardrum) Ans: Thin elastic sheet.
© 2025 All rights reserved
, 3 | Page
Middle ear Ans: Eustachian tube
Tensor tympani
Stapedius
Ossicles:
Malleus (hammer)
Incus (anvil)
Stapes (stirrup)
Eustachian tube Ans: Connects the middle ear with the pharynx.
Equalizes air pressure on either side of the eardrum
Tensor tympani and Stapedius Ans: Muscles attached to the
malleus and stapes
Incus (anvil) Ans: The middle bone which is connected to the
malleus and hammer, passes vibrations onto the stapes.
Ossicles Ans: 3 small bones in the middle ear that conduct sound
mechanically, goal is to amplify sounds
Malleus (hammer) Ans: Affixed to the tympanic membrane and
acts on the incus
© 2025 All rights reserved
