Exam 2

Question 1

What are the four scales of measurement?

Answer 1

• Nominal: Classifies data into categories
• Ordinal: Ranks data without equal intervals
• Interval: Equal intervals between values but no absolute zero
• Ratio: Includes an absolute zero, allowing meaningful comparisons

Question 2

Define nominal scale.

Answer 2

Classifies data into categories, such as blood type or hearing sensitivity.

Question 3

Define ordinal scale.

Answer 3

Ranks data without equal intervals, such as severity of a disorder.

Question 4

Define interval scale.

Answer 4

Has equal intervals between values but no absolute zero, such as IQ scores.

Question 5

Define ratio scale.

Answer 5

Includes an absolute zero, allowing meaningful comparisons, such as height, weight, age, or intensity.

Question 6

What is the base in an equation?

Answer 6

The number being multiplied.

Question 7

What is the exponent in an equation?

Answer 7

Indicates how many times the base is multiplied by itself.

Question 8

What is the rule for multiplying exponents?

Answer 8

Add exponents when the base is the same.

Question 9

What is the rule for dividing exponents?

Answer 9

Subtract exponents when the base is the same.

Question 10

2 Sources & Same Intensity

Answer 10

Add 3

Question 11

Multiple Sources & Same Intensities

Answer 11

Every doubling is an increase of 3

16 Sources would be 2x2x2x2 So I would add 12 because 3*4 =12

Question 12

Unequal Source Intensities

Answer 12

Add 0.4 to the highest value

Question 13

What is the reference for dB IL?

Answer 13

10^-12 watt/m².

Question 14

What is the reference for dB SPL?

Answer 14

20 µPa.

Question 15

What are the units of measurement for sound intensity?

Answer 15

• N/m²
• Pa
• dyne/cm²

Question 16

What is the formula for sound intensity level (dB IL)?

Answer 16

Level = Ix/Ir or log10(Ix/Ir).

Question 17

What is the formula for sound pressure level (dB SPL)?

Answer 17

Level = 20 log10(Px/Pr).

Question 18

What happens to dB when intensity doubles? (dB IL)

Answer 18

Increases by 3 dB.

Question 19

What happens to dB when pressure doubles? (dB SPL)

Answer 19

Increases by 6 dB.

Question 20

What happens to dB with a tenfold increase in intensity?

Answer 20

Increases by 10 dB.

Question 21

How do dB IL and dB SPL relate?

Answer 21

They are equal in value but reference different physical properties.

Question 22

What does a positive dB value indicate?

Answer 22

Sound is above the reference level.

Question 23

What does a negative dB value indicate?

Answer 23

Sound is below the reference level.

Question 24

What does 0 dB signify?

Answer 24

Sound is at the reference level, not an absence of sound.

Question 25

Define absolute acoustic power.

Answer 25

The actual power of a sound wave.

Question 26

Define relative acoustic power.

Answer 26

The power ratio between two waves.

Question 27

What is reference power?

Answer 27

The baseline against which relative power is measured.

Question 28

What is a bel?

Answer 28

Unit of measure for relative intensity.

Question 29

What is a decibel (dB)?

Answer 29

1/10 of a bel, used to reduce large numerical values.

Question 30

How does intensity affect the tympanic membrane?

Answer 30

Higher intensity increases eardrum displacement.

Question 31

How do frequency changes affect the tympanic membrane?

Answer 31

They affect how the eardrum vibrates.

Question 32

What is one way to overcome impedance in sound transmission?

Answer 32

Area ratio advantage: The tympanic membrane is larger than the oval window.

Question 33

What is the lever action of ossicles?

Answer 33

The malleus and incus amplify sound through a mechanical lever.

Question 34

What is the buckling motion of the tympanic membrane?

Answer 34

Increases force transmitted to the ossicles.

Question 35

How is intensity determined in the cochlea?

Answer 35

Encoded by the amplitude of basilar membrane movement.

Question 36

How is frequency determined in the cochlea?

Answer 36

Determined by the location of maximum displacement along the basilar membrane.

Question 37

Where on the basilar membrane are high-frequency sounds detected?

Answer 37

Base of cochlea.

Question 38

Where on the basilar membrane are low-frequency sounds detected?

Answer 38

Apex of cochlea.

Question 39

Why does the base of the cochlea detect high-frequency sounds?

Answer 39

Due to differences in stiffness and mass along the basilar membrane.