QUIZ 2

Question 1

what are the 3 elements of acoustics

Answer 1

sound, ambience, music

Question 2

the sensation stimulated in the organs of hearing by mechanical radiant energy transmitted as longitudinal pressure waves through the air or other medium vibration in an elastic medium

Answer 2

sound

Question 3

the type of sound that is considered to be desirable

Answer 3

?

Question 4

a measure of the acoustics energy emitted from a noise source, expressed in decibels

Answer 4

sound power

Question 5

the power carried by sound waves per unit area in a direction perpendicular to that area

Answer 5

sound intensity

Question 6

the unit of the sound pressure level

Answer 6

pascal

Question 7

a longitudinal pressure wave in air or elastic medium esp. one producing an audible sensation

Answer 7

sound wave

Question 8

the no. of times the cycle of compression and rarefaction of air occurs in a given unit of time

Answer 8

frequency

Question 9

transmission of sound is primarily retarded by the barrier’s ____ & ____

Answer 9

mass & stiffness

Question 10

the log ratio of the incident energy to the transmitted energy

Answer 10

sound transmission energy

Question 11

a score given to a building’s surface based on it ability to reduce sound coming through it

Answer 11

sound transmission class

Question 12

an STC rating that is considered to have a very poor performance that even low speech is audible

Answer 12

20-25db

Question 13

an STC rating that is considered have good performance where loud speech heard is hardly understood

Answer 13

35-40db

Question 14

an NRC rating of ___ absorbs all sound

Answer 14

1

Question 15

an NRC rating of ___ absorbs no sound

Answer 15

0

Question 16

the passage of sound from one room to another or from the exterior into a room in a building

Answer 16

sound transmission

Question 17

used to evaluate the sound absorption efficiency of materials. It is the ratio of absorbed energy to incident energy and is represented by a.

Answer 17

sound absorption coefficient

Question 18

give 3 kinds of sound absorbers

Answer 18

porous, membrane & resonance

Question 19

the change of direction that a ray of sound undergoes when it strikes a surface

Answer 19

sound reflection

Question 20

defines the refraction angle corresponding to the transmitted waves

Answer 20

snell’s law

Question 21

whereby a sound wave moves around an object whose dimensions are smaller that or about equal to the wavelength of the sound

Answer 21

sound diffraction

Question 22

the persistence of sound after it has been stopped due to multiple reflections from surface such as furniture, people, air etc. within a closed surface

Answer 22

sound reverberation

Question 23

the repetition of sound cause by reflection of sound waves from a hard surface back to the listener

Answer 23

sound echo

Question 24

an acoustical defect occurs if there are two parallel reflecting walls

Answer 24

flutter echo

Question 25

result of the sound foci which causes the sound intensity in certain areas to be so low that is its already insufficient for hearing

Answer 25

dead spots