IHS Chapter 4 Test Questions and
Correct Answers
What effect does a 10 dB SPL increase in intensity have on the sensation of loudness
over the most of the audible range ✅increases by double
How does Boyle's law apply to hearing aid fittings? ✅fitting depth affects the sound
pressure level at the eardrum
A HA Specialist is presenting a tone to a PT. They want to be sure that the PT hears the
tone, so they present it at a level that is 20dB above the PT's threshold at 1000 HZ,
which is 30dB HL. How should the HA Specialist notate this presentation level? ✅20
dB SL
Which frequency of pure tone will be perceived as the loudest when presented at 60dB
SPL? ✅1000 Hz
A PT comes in for Hearing Test. They indicate they have a lot of trouble distinguishing
between speech sounds like "ith" and "if" as well as hearing background noise.
Which factor may be causing this PT's challenges? ✅widening critical bands
PT is in office for a 6month F\U appt. They state they are generally very happy with
HA's, but they are having trouble in conference area at work as it is in a large room with
hard surfaces.
What acoustic principle can be applied to decrease PT's difficulty? ✅absorption
when Two 40 dB SPL sounds are combined what is the resulting dB SPL? ✅46 dB
SPL
Intensity and frequency are the perpetual matches for which of the following
✅loudness and pitch
what is the dividing line between low and high frequencies ✅1000 Hz
HA Specialist strikes a tuning fork, which begins to vibrate and emit a sound. How do
the sound waves created by the fork affect the air through which they travel ✅the
waves move the air molecules through compression and rarefaction
What is the range of human hearing in dynes\cm2 and decibels? ✅0.0002 to 1000; 0
to 140
Correct Answers
What effect does a 10 dB SPL increase in intensity have on the sensation of loudness
over the most of the audible range ✅increases by double
How does Boyle's law apply to hearing aid fittings? ✅fitting depth affects the sound
pressure level at the eardrum
A HA Specialist is presenting a tone to a PT. They want to be sure that the PT hears the
tone, so they present it at a level that is 20dB above the PT's threshold at 1000 HZ,
which is 30dB HL. How should the HA Specialist notate this presentation level? ✅20
dB SL
Which frequency of pure tone will be perceived as the loudest when presented at 60dB
SPL? ✅1000 Hz
A PT comes in for Hearing Test. They indicate they have a lot of trouble distinguishing
between speech sounds like "ith" and "if" as well as hearing background noise.
Which factor may be causing this PT's challenges? ✅widening critical bands
PT is in office for a 6month F\U appt. They state they are generally very happy with
HA's, but they are having trouble in conference area at work as it is in a large room with
hard surfaces.
What acoustic principle can be applied to decrease PT's difficulty? ✅absorption
when Two 40 dB SPL sounds are combined what is the resulting dB SPL? ✅46 dB
SPL
Intensity and frequency are the perpetual matches for which of the following
✅loudness and pitch
what is the dividing line between low and high frequencies ✅1000 Hz
HA Specialist strikes a tuning fork, which begins to vibrate and emit a sound. How do
the sound waves created by the fork affect the air through which they travel ✅the
waves move the air molecules through compression and rarefaction
What is the range of human hearing in dynes\cm2 and decibels? ✅0.0002 to 1000; 0
to 140
