Quiz 1 + Midterm

Question 1

What’s the difference between longitudinal and transverse waves?

Answer 1

Longitudinal:

• sound in air
• pressure wave
• particles vibrate in the same or opposite direction of propagation–away from/toward source
• approaching/receding waves create pressure variations

Transverse:

• dropping a rock in water
• not a pressure wave in the same way
• particles vibrate at right angles to direction of the wave
• bobbing up + down as wave moves

Question 2

Simple Harmonic Motion

Answer 2

• a predictable, repeating pattern of vibration resulting in a pure tone
• constant frequency
• graphic representation is a sine wave
• periodic

Question 3

Periodic vs Aperiodic

Answer 3

Periodic:

• similar to Simple Harmonic Motion
• a simple, repeating, regular, pure tone

Aperiodic:

• vibration w/ no repetitive patterns: irregular periods
• white noise, speech, busy street, etc
• aka complex sound

Question 4

Frequency

Answer 4

• cycles per second (Hz)
• inversely related to period: if freq = 20hz, period = 1/20 a second
• frequency can remain the same while amplitude changes

Question 5

Decibel

Answer 5

-measurement of intensity between 2 sounds

• logarithmic scale based on exponents of 10
• -condenses large range of human aural sensitivity into manageable scale
• -10,000,000,000,000 vs 10^13 (130 db)
• -corresponds to how intensity differences are perceived

-there’s a big complicated formula involving watt outage and intensity referents

Question 6

What are the 5 components of language?

Answer 6

phonology, morphology, syntax, semantics, pragmatics

Question 7

What is a complex sound?

Answer 7

• a sound with a lot of variation in its wave form, irregular, not repetitive
• opposite of simple/pure tone

Question 8

Forces of Simple Harmonic Motion

Answer 8

Elasticity: SHM has a restoring force generated by elasticity

• medium goes back to resting position
• TLDR: slows tines of a tuning fork down when displaced

Inertia: as the medium goes back to resting, inertia overshoots and elasticity/RF builds up again

• this continues, maintaining wave
• TLDR: causes tines to pass resting and continue moving

-these work simultaneously

Question 9

Semantics

Answer 9

-governs meaning of content of words and word combos

Question 10

What is thought? How does it relate to language?

Answer 10

• thought is an internal representation of experiences
• language is used to express thoughts, language aids thought but isn’t necessary to think
• lang. is a vessel for thought and a reflection of thought, but doesn’t determine thought

Question 11

Period

Answer 11

• time in seconds to complete a cycle i.e. 1/20th, 1/3

- inversely related to frequency: 1/20th = 20 hz frequency

Question 12

Interference

Answer 12

• multiple waves in medium
• -simultaneous sounds = multiple wave patterns
• -complex sounds = multiple frequencies simultaneously
• -waves bounce off objects, set up reflected waves

-waves in medium combine w/ simple addition

• patterns of constructive and destructive interference result
• -sound can cancel out sound
• -dependent on whether waves are in sync

Question 13

Amplitude

Answer 13

• related to intensity (loudness)

- y-axis of waveforms

Question 14

How do you find the harmonics if given the fundamental frequency?

Answer 14

• the fundamental frequency (F0) is the first harmonic (H1)
• second harmonic (H2) is first harmonic times 2
• simple multiples
• if F0=H1=100hz, H2=200hz, H3=300hz, etc