Building Services Engineering 5th Edition Handbook

Room acoustics 345
4. A church presbytery committee.
5. Temporary shift in hearing ability from exposure to high industrial noise levels above
95 dBC.
36. Hearing range is:
1. 20 Hz to 20 kHz.
2. 2 Hz to 20 MHz.
3. 200 Hz to 200 MHz.
4. Infinitely wide.
5. 2 kHz to 20 MHz.
37. What is noise?
1. Sound.
2. Acoustic power.
3. Unwanted sound.
4. Age-related sound.
5. Traffic, aeroplanes, pneumatic drills, fans, refrigeration compressors.
38. How do we judge sound?
1. With absolute measurement.
2. Comparing a sound with absolute zero sound level.
3. Relatively.
4. Subjectively.
5. Qualitative judgement.
39. What is sound?
1. Electromagnetic radiation.
2. Molecular vibration of solid materials.
3. Radio frequency waves.
4. Anything that causes an ear response.
5. Pressure waves.
40. Sound travels through air because it is:
1. Incompressible.
2. Supporting molecular vibration.
3. Compressible.
4. Inelastic.
5. Plastic.
41. Reference point for sound level measurement is:
1. Absolute zero sound.
2. Lowest audible level by a domestic animal.
3. Smallest sound detectable by human ear.
4. Zero atmospheric pressure as found in space.
5. Inaudible level created in a test laboratory.
42. Sound waves repeat at a frequency due to:
1. Absorption by porous surfaces.
2. Wind forces.