OHS 621 FINAL EXAM (6-11) | ACE EVERY TEST |
100% VERIFIED ANSWERS INSIDE.
DEFINE Sound - Answer: a) Produced in the air by 'oscillations' in air pressure (sound
waves)
b) Converts into electrical signal & perceived as sensory experience by brain
How do sound waves BEHAVE? - Answer: - Sound passes via solid, liquid, gas
- Can be reflected, diffracted, interfered
CHARACTERISTICS of Sound? - Answer: Amplitude & Frequency
DEFINE Frequency/Pitch: - Answer: - # of waves at ear per secs. OR # of cycles/secs.
waves move (measured in cps or hz)
- Wavelength or lambda (λ)
Frequency Waves (few/many) - Answer: *FEW Waves = LOW Pitch
*MANY Waves = HIGH Pitch
Frequency (high/low wavelength) - Answer: *HIGH Frequency = SHORT Wavelength
*LOW Frequency = LONG Wavelength
Frequency FORMU LA - Answer: *F = C/λ*
- F = frequency of sound (cycles/sec.)
- C = speed of sound (m/sec.)
- λ = wavelength of sound (m)
1
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,How Fast Does Sound Travel? - Answer: 344 m/sec. @20*C & 1100 ft./sec
DEFINE Amplitude - Answer: "intensity or loudness" [measured in newtons per sq.m
(m2) or pascals (Pa)]
*1 Pa = 1 N/m2*
Amplitude (great amplitude = ?) - Answer: GREATER Amplitude = LOUDER Sound
How much can the human ear hear? (amplitude) - Answer: 0.00002 - 200 Pa
Amplitude (low/upper limit) - Answer: *LOW Limit = threshold of HEARING
*UPPER Limit = threshold of PAIN
DEFINE Soundwave - Answer: pressure variations above/below atmospheric pressure
Amplitude Measurement Unit: (dB) - Answer: - Loudness of sound is expressed in
decibels (dB)
Sound Pressure Level (Lp) FORMULA : (Amplitude) - Answer: *Lp = 20 log P/Po*
- Lp = sound pressure level (dB)
- P = sound pressure (Pa)
- Po = threshold of hearing of avg. person @1000 Hz (0.00002 Pa)
DEFINE Noise - Answer: An unwanted, disagreeable, disturbing sound
OHS CONCERNS of Noise - Answer: - Hearing loss
2
APPHIA - Crafted with Care and Precision for Academic Excellence.
, - Increased stress, nervousness, fatigue
- Interfere with speech/communication
- Synergic effects of VOC & CO
TYPES of Noise (3) - Answer: 1) Continuous
2) Intermittent
3) Impact/Impulse (0.5 secs. with >1 sec. interval)
Ontario 85dB Exposure Level & Exchange Rate - Answer: PEL = 85 dB for 8hrs.
Exchange Rate = 3 dB
Ontario 90dB Exposure Level & Exchange Rate - Answer: PEL = 90 dB for 8 hrs.
Exchange Rate = 5 dB
DESCRIBE Noise Dosimeter: - Answer: - Meter placed 9in. to ear/shoulder of worker to
determine personal exposure level
- Measures TWA of noise energy
COMPONENTS of Outer Ear (1) - Answer: 1) PINNA: (ear flap)
- catch soundwave + increase ability to hear
2) EXTERNAL AUDITORY CANAL:
- filter particles + wax for infection protection
- leads to eardrum
- transmits energy to middle ear (from gas --> solid)
COMPONENTS of Middle Ear (2) - Answer: 1) OSSICLES:
3
APPHIA - Crafted with Care and Precision for Academic Excellence.
100% VERIFIED ANSWERS INSIDE.
DEFINE Sound - Answer: a) Produced in the air by 'oscillations' in air pressure (sound
waves)
b) Converts into electrical signal & perceived as sensory experience by brain
How do sound waves BEHAVE? - Answer: - Sound passes via solid, liquid, gas
- Can be reflected, diffracted, interfered
CHARACTERISTICS of Sound? - Answer: Amplitude & Frequency
DEFINE Frequency/Pitch: - Answer: - # of waves at ear per secs. OR # of cycles/secs.
waves move (measured in cps or hz)
- Wavelength or lambda (λ)
Frequency Waves (few/many) - Answer: *FEW Waves = LOW Pitch
*MANY Waves = HIGH Pitch
Frequency (high/low wavelength) - Answer: *HIGH Frequency = SHORT Wavelength
*LOW Frequency = LONG Wavelength
Frequency FORMU LA - Answer: *F = C/λ*
- F = frequency of sound (cycles/sec.)
- C = speed of sound (m/sec.)
- λ = wavelength of sound (m)
1
APPHIA - Crafted with Care and Precision for Academic Excellence.
,How Fast Does Sound Travel? - Answer: 344 m/sec. @20*C & 1100 ft./sec
DEFINE Amplitude - Answer: "intensity or loudness" [measured in newtons per sq.m
(m2) or pascals (Pa)]
*1 Pa = 1 N/m2*
Amplitude (great amplitude = ?) - Answer: GREATER Amplitude = LOUDER Sound
How much can the human ear hear? (amplitude) - Answer: 0.00002 - 200 Pa
Amplitude (low/upper limit) - Answer: *LOW Limit = threshold of HEARING
*UPPER Limit = threshold of PAIN
DEFINE Soundwave - Answer: pressure variations above/below atmospheric pressure
Amplitude Measurement Unit: (dB) - Answer: - Loudness of sound is expressed in
decibels (dB)
Sound Pressure Level (Lp) FORMULA : (Amplitude) - Answer: *Lp = 20 log P/Po*
- Lp = sound pressure level (dB)
- P = sound pressure (Pa)
- Po = threshold of hearing of avg. person @1000 Hz (0.00002 Pa)
DEFINE Noise - Answer: An unwanted, disagreeable, disturbing sound
OHS CONCERNS of Noise - Answer: - Hearing loss
2
APPHIA - Crafted with Care and Precision for Academic Excellence.
, - Increased stress, nervousness, fatigue
- Interfere with speech/communication
- Synergic effects of VOC & CO
TYPES of Noise (3) - Answer: 1) Continuous
2) Intermittent
3) Impact/Impulse (0.5 secs. with >1 sec. interval)
Ontario 85dB Exposure Level & Exchange Rate - Answer: PEL = 85 dB for 8hrs.
Exchange Rate = 3 dB
Ontario 90dB Exposure Level & Exchange Rate - Answer: PEL = 90 dB for 8 hrs.
Exchange Rate = 5 dB
DESCRIBE Noise Dosimeter: - Answer: - Meter placed 9in. to ear/shoulder of worker to
determine personal exposure level
- Measures TWA of noise energy
COMPONENTS of Outer Ear (1) - Answer: 1) PINNA: (ear flap)
- catch soundwave + increase ability to hear
2) EXTERNAL AUDITORY CANAL:
- filter particles + wax for infection protection
- leads to eardrum
- transmits energy to middle ear (from gas --> solid)
COMPONENTS of Middle Ear (2) - Answer: 1) OSSICLES:
3
APPHIA - Crafted with Care and Precision for Academic Excellence.
